{"id":30844,"date":"2026-03-26T14:08:00","date_gmt":"2026-03-26T18:08:00","guid":{"rendered":"https:\/\/www.litmus.com\/?p=30844"},"modified":"2026-06-08T07:45:34","modified_gmt":"2026-06-08T11:45:34","slug":"email-ab-testing-how-to","status":"publish","type":"post","link":"https:\/\/www.litmus.com\/blog\/email-ab-testing-how-to","title":{"rendered":"Mastering Email A\/B Testing: The Difference Between Good vs Great"},"content":{"rendered":"\n\n\t<div id=\"simple-text-block-block_5d9af24e4cdbb2f0c87c298065c33b79\" class=\"block-simple-text-block alignfull \" style=\"background-color:\">\n  <div class=\"container\">\n  \t<div class=\"row\">\n  \t\t<div class=\"col\">\n  \t\t\t<div class=\"copy\">\n  \t\t\t\t<table style=\"background-color: #f2f3f6;\">\n<tbody>\n<tr>\n<td class=\"block-1\" style=\"padding: 20px;\">\n<h3>Key takeaways \u2728<\/h3>\n<ul>\n<li><strong>Email A\/B testing helps marketers<\/strong> make smarter decisions by swapping one element at a time\u2014like a subject line, CTA, or send time\u2014and learning what actually resonates with their audience.<\/li>\n<li><strong>To get meaningful results<\/strong>, you need a clear hypothesis, a randomized sample size of at least 10,000 people, and enough time for results to stabilize.<\/li>\n<li><strong>Avoid common pitfalls<\/strong> like testing too many variables at once, calling a winner too early, or forgetting to document and roll out your findings.<\/li>\n<li><strong>If you can create it, you can test it.<\/strong> Play with subject lines, personalization, design, automation timing, or body copy to optimize engagement and conversions over time.<\/li>\n<li><strong>Successful email marketing programs<\/strong> use A\/B testing as an ongoing practice to challenge assumptions, experiment quickly, and apply insights to future campaigns.<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>&nbsp;<\/p>\n<p><iframe title=\"YouTube video player\" src=\"https:\/\/www.youtube.com\/embed\/KVu2uZ8eVwc?si=zfbjU5yKOSrf59i4&amp;start=1051\" width=\"560\" height=\"315\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe> <script type=\"application\/ld+json\">{\n  \"@context\": \"http:\/\/schema.org\",\n  \"@type\": \"VideoObject\",\n  \"name\": \"[Holistic Testing Methodology] How to Set Up Email A\/B Tests\",\n  \"description\": \"Discover the power of the Holistic Testing Methodology in email marketing with Kath Pay, Co-Founder and Author at Holistic Email Marketing.  Learn how to set up email A\/B tests that go beyond superficial tweaks to test deeper motivations and personas. She also walks you through a detailed case study to show how to put what you have learned into action.  Recording titled \\\"Strategic Testing for Long-Term Impact: A Case Study in Holistic A\/B Testing\\\" from Litmus Live 2024. #LitmusLive2024 ___  \ud83d\udca1 Litmus Live is an annual, multi-day virtual event packed with sessions and panels hosted by experts who live and breathe all things email marketing.  \ud83d\udcbb Watch more Litmus Live sessions: https:\/\/lit.ms\/litmus-live   \ud83d\udc40 Read our 2024 Litmus Live Recap: https:\/\/lit.ms\/4hV5zMr  \u270f\ufe0f Learn about Litmus Live: https:\/\/lit.ms\/4fDadwQ\",\n  \"thumbnailUrl\": \"https:\/\/i.ytimg.com\/vi\/KVu2uZ8eVwc\/default.jpg\",\n  \"uploadDate\": \"2024-12-02T12:00:22Z\",\n  \"duration\": \"PT28M7S\",\n  \"embedUrl\": \"https:\/\/www.youtube.com\/embed\/KVu2uZ8eVwc\",\n  \"interactionCount\": \"39\"\n}<\/script><\/p>\n<p>At Litmus, we\u2019re constantly testing emails. It\u2019s kinda what we\u2019re known for \ud83d\ude09. Most of the time, we\u2019re talking about pre-send testing\u2014previewing your email on hundreds of email clients and devices to see how it appears before your subscribers receive it.<\/p>\n<p>But there\u2019s another type of testing that\u2019s almost as important: A\/B testing.<\/p>\n<p>This takes place after you send your email and is usually done through your email service provider (ESP).<\/p>\n<p>If you\u2019re tired of making email marketing decisions based on hunches (or trying to get buy-in for your plans), then running an A\/B test can give you more insight into how your audience responds to different design, copy, and strategic choices. With a bit of foresight and planning, you can turn your gut feelings and ideas into real data to share with the entire team. In this post, we\u2019ll cover:<\/p>\n<h2>Table of contents<\/h2>\n<ul>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#what-ab\">What is email A\/B testing?<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#why-ab\">Why A\/B testing fuels better email decision-making<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#mistakes\">How to dodge common A\/B testing mistakes<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#set-up\">How to set up and run efficient A\/B tests<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#elements\">What elements to A\/B test in your emails<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#not-test\">When you should NOT run an A\/B test<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#enterprise\">Mastering enterprise AB testing<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#brands\">How popular brands run A\/B tests<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#popular-tools\">Popular email marketing A\/B testing tools<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#before-launch\">Before you launch your first email A\/B test<\/a><\/li>\n<li aria-level=\"1\"><a rel=\"noopener\" href=\"#litmus\">Take the guesswork out of your testing strategy with Litmus<\/a><\/li>\n<\/ul>\n<h2 id=\"what-ab\">What is email A\/B testing?<\/h2>\n<p>Email A\/B testing, also known as split testing, is the process of creating two versions of the same email with one variable changed, like swapping out a subject line or applying <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/contextual-targeting-vs-behavioral-targeting\">behavioral targeting<\/a>. Then, you send that email to two subsets of an audience to see which version performs best.<\/p>\n<p>In other words: email A\/B testing pits two emails against each other to see which is superior. You can test elements that are big or small to gain <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/customer-data-management-guide-for-marketers\">customer insights<\/a> that help you do things like:<\/p>\n<ul>\n<li aria-level=\"1\">Update your email design.<\/li>\n<li aria-level=\"1\">Learn about your audience\u2019s preferences.<\/li>\n<li aria-level=\"1\">Improve email performance.<\/li>\n<\/ul>\n<p>You don\u2019t always have to A\/B test your emails, says Camila Espinal, Email Marketing Manager at Validity. \u201cA\/B testing is a great choice when engagement is your primary goal,\u201d she says. \u201cYou\u2019ll want to choose campaigns with large audiences, like your newsletter or a promotional send, and it should be a repeatable campaign where those insights can be applied again.\u201d<\/p>\n<h2 id=\"why-ab\">A\/B testing fuels better decisions for email marketers<\/h2>\n<p>It\u2019s an extra step to add A\/B testing to your email production process, but it\u2019s a worthwhile one if you\u2019re trying to maximize revenue from your email marketing program. Says Espinal, \u201cIt gives you the data you need so you can step away from taking a shot in the dark and use real information to sharpen your campaigns, improve engagement, and connect with your audience. You can definitively shift away from what doesn\u2019t work so you\u2019re no longer wasting your time creating campaigns that your customers or prospects aren\u2019t interested in, and instead double down on the things that resonate with them.\u201d<\/p>\n<p>It adds a scientific element to your email marketing process so you can prove your email ROI instead of hoping for the best. When we asked email marketers how they improved the already-great 36:1 ROI from email marketing, 12% cited A\/B testing as a key part of their strategy.<\/p>\n<figure id=\"attachment_120031\" aria-describedby=\"caption-attachment-120031\" style=\"width: 1024px\" class=\"wp-caption alignnone\"><img decoding=\"async\" class=\"wp-image-120031 size-large\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/overall-business-goals-1024x765.png\" alt=\"Email's contribution to overall business goals chart\" width=\"1024\" height=\"765\" srcset=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/overall-business-goals-1024x765.png 1024w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/overall-business-goals-300x224.png 300w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/overall-business-goals-768x574.png 768w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/overall-business-goals.png 1328w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption id=\"caption-attachment-120031\" class=\"wp-caption-text\">Source: <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/infographic-the-roi-of-email-marketing\">The ROI of email marketing infographic <\/a><\/figcaption><\/figure>\n<p>&nbsp;<\/p>\n<p>\u201cSometimes, you can get really stuck on \u2018Oh, it\u2019s what we\u2019ve always done,\u2019\u201d adds Espinal. \u201cOne of the best parts of email marketing is having the opportunity to try something new, and use data to measure that impact.\u201d<\/p>\n<p>A\/B testing starts with coming up with a clear hypothesis: What do you think will happen if you change element X? From there, you can test it out and take that information to move forward with a new design or strategy that can dramatically impact your bottom line.<\/p>\n<p>Espinal adds, \u201cYou don&#8217;t know what works until you try.\u201d<\/p>\n\n<div class=\"container pt-3 pb-5 px-1\">\n\t<div class=\"row blog-cta-blue rounded-5 p-4\">\n\t\t<div class=\"mx-auto col-12\">\n\t\t\t<div class=\"row d-flex align-items-center\">\n\t\t\t<div class=\"col-lg-6 col-12\">\n\t\t\t\t<p class=\"bold fs-4\">Email trends that truly matter<\/p>\n\t\t\t\t<p>Separate hype from reality with The State of Email Trends Report. Learn which trends to adopt and why.\n<\/p>\n\t\t\t\t<button class=\"button-blue download\"><a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/state-of-email-reports\" class=\"text-white text-decoration-none\">Explore trends now<\/a><\/button>\n\t\t\t<\/div><!--col-6-->\n\t\t\t<div class=\"col-6 d-none d-lg-block\">\n\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2024\/09\/download-blog-cta-09232024.svg\" width=\"221\" height=\"175\" alt=\"\">\n\t\t\t<\/div><!--col-6-->\n\t\t\t<\/div> <!--row-->\n\t\t<\/div><!--col-12-->\n\t<\/div><!--row-->\n<\/div><!--container-->\n\t\n\t\n\t\n\t\n\n<h2 id=\"mistakes\">How to dodge 5 common email marketing A\/B testing mistakes<\/h2>\n<p>Okay, email geeks. It\u2019s time to put your scientist hat on. For A\/B testing, you need to think like a scientist\u2014which means choosing what you test, when you test, and how you test very carefully. Making one of these common mistakes can blow the entire test, making you think you\u2019ve nailed down a great email marketing strategy only to get stuck with the same\u2014or worse\u2014results in your next send.<\/p>\n<p>Avoid common mistakes like:<\/p>\n<h3>1. Testing too much at one time<\/h3>\n<p>If you try to test more than one element of your email\u2026how will you know which element directly impacted the outcome?<\/p>\n<p>The answer is you won\u2019t. So even though you might be tempted to swap out a subject line AND a CTA AND your design in the same test to pit two emails against each other, resist the urge! Careful, incremental testing will get you where you need to go. \u201cIf you want to test multiple elements, you can use multivariate testing, but it requires a very large audience to make it work,\u201d says Espinal.<\/p>\n<p>This kind of test-everything mentality often comes from a deeper issue: Not having a clear hypothesis in the first place. You must have a defined goal in mind, with the matching metrics to measure, to determine the winner. \u201cEven if one version performs better, you won\u2019t learn why without a strong hypothesis,\u201d adds Espinal. \u201cIt should be an if\/then statement, like \u2018If we change this subject line, then we\u2019ll see more opens because it creates a sense of urgency.\u2019\u201d<\/p>\n<h3>2. Running tests with too small a sample<\/h3>\n<p>When you do run a test, it needs to be with a statistically significant, randomized audience. That means it has to be large enough and random enough where you know for sure that whatever changes you made had an impact and you\u2019re not nitpicking between decimal points.<\/p>\n<p>\u201cWith only a few hundred contacts, the results won\u2019t reach statistical significance, so the outcome is unreliable,\u201d says Espinal. \u201cYou should aim for 10,000 people or more on a test if you can. Similarly, you can\u2019t assume one version won just because it\u2019s slightly ahead, like 22% opens for version A vs. 21% opens in version B. That\u2019s not a clear winner.\u201d<\/p>\n<p>An A\/B testing calculator can help determine the required sample size, and if the audience is too small, test only big, sweeping changes or use sequential tests to get a better sense of what\u2019s working and what\u2019s not. Aim for 95% confidence (p &lt; 0.05) before declaring a winner, and if you\u2019re not able to do that, run the test again.<\/p>\n<p>Then, use your ESP to make sure it\u2019s a random split, rather than testing existing segments (like a West Coast vs. East Coast audience split) to remove any potential bias from the differences in your audience. Otherwise, you won\u2019t be able to isolate the variable you\u2019re using against built-in preferences from your audience.<\/p>\n<h3>3. Funky test timing<\/h3>\n<p>You may be anxious to see the results, but an A\/B test takes at least 48 hours to run its course, and even then, you may want to wait longer to achieve statistical significance. \u201cIt takes a while for people to get through their inbox,\u201d says Espinal. \u201cMake sure you\u2019re allowing enough time for people to see the email before calling a winner.\u201d<\/p>\n<p>Early results can flip-flop wildly, so you risk a false positive on a variant without defining the test duration up front with your team. From there, it\u2019s up to you to decide if you want to run a confirmation test with a future email or move forward with the results.<\/p>\n<p>Similarly, make sure you\u2019re testing outside of major promotions, holidays, or news events to avoid unusual behavior that can skew the results. \u201cUnless you\u2019re testing seasonal messaging, you should always try to run an A\/B test under the conditions you want to replicate the results in,\u201d says Espinal. \u201cUnusual behavior won\u2019t reflect normal campaigns, so you can\u2019t use the results of that test.\u201d<\/p>\n<h3>4. Forgetting about rolling out the results<\/h3>\n<p>You\u2019ve put in all that effort to create the test\u2014now make sure you\u2019re documenting and actually using the results. \u201cLog the hypothesis, outcome, and insight for every test,\u201d says Espinal. \u201cOtherwise, you\u2019ll just repeat your mistakes. I keep a central A\/B test log with test details and outcomes so I know what to do for my next campaign.\u201d<\/p>\n<p>Turn the insights that you get from your hard work into playbooks and guidelines as you move forward with future campaigns. That way, instead of following the same \u201cbest practices\u201d that everyone uses, you know exactly what works for your audience\u2014whether it\u2019s shorter subject lines or chatty ones, sending on Tuesdays or Wednesdays, or making your CTA buttons black instead of orange.<\/p>\n<table class=\"table table-striped\">\n<thead>\n<tr>\n<th>A\/B Testing Mistake<\/th>\n<th>Impact<\/th>\n<th>How to Avoid It<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Testing too much at once<\/td>\n<td>It\u2019s impossible to isolate what actually worked.<\/td>\n<td>Test only one element of your emails at a time.<\/td>\n<\/tr>\n<tr>\n<td>Using a sample size that\u2019s too small<\/td>\n<td>Without randomizing a large sample size, you won\u2019t achieve statistical significance so you can\u2019t choose a winner.<\/td>\n<td>Test with random splits of 10,000 people or more.<\/td>\n<\/tr>\n<tr>\n<td>Calling a winner too early or during \u201coff\u201d times<\/td>\n<td>It takes time to get the results of a test and reach statistical significance so you can know which version truly won.<\/td>\n<td>Wait 48\u201372 hours before calling the result. If there\u2019s a major news event or holiday, wait to run the test.<\/td>\n<\/tr>\n<tr>\n<td>Forgetting about the results<\/td>\n<td>Failing to document and then roll out those changes defeats the purpose of running an A\/B test in the first place.<\/td>\n<td>Document all of your learnings and roll out changes in future email campaigns.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n<div class=\"container pt-3 pb-5 px-1\">\n\t<div class=\"row blog-cta-blue rounded-5 p-4\">\n\t\t<div class=\"mx-auto col-12\">\n\t\t\t<div class=\"row d-flex align-items-center\">\n\t\t\t<div class=\"col-lg-6 col-12\">\n\t\t\t\t<p class=\"bold fs-4\">Email trends that drive results<\/p>\n\t\t\t\t<p>Dive into the State of Email Report for insights from marketers worldwide. Get the latest trends and best practices. <\/p>\n\t\t\t\t<button class=\"button-blue download\"><a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/state-of-email-reports\" class=\"text-white text-decoration-none\">Get the report<\/a><\/button>\n\t\t\t<\/div><!--col-6-->\n\t\t\t<div class=\"col-6 d-none d-lg-block\">\n\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2024\/09\/download-blog-cta-09232024.svg\" width=\"221\" height=\"175\" alt=\"\">\n\t\t\t<\/div><!--col-6-->\n\t\t\t<\/div> <!--row-->\n\t\t<\/div><!--col-12-->\n\t<\/div><!--row-->\n<\/div><!--container-->\n\t\n\t\n\t\n\t\n\n<h2 id=\"set-up\">How to set-up and run effective email A\/B tests<\/h2>\n<p>While email A\/B testing is straightforward in theory, it can have a lot of moving parts. If you want to <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/ab-testing-foundation\/\">get accurate insights<\/a> to share with your team, invest a little time planning and analyzing.<\/p>\n<p>Below are the steps you need to take to <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/how-the-worlds-best-email-brands-run-a-b-tests\/\">run a successful (and insightful) A\/B test<\/a>.<\/p>\n<h3>1. Choose an objective<\/h3>\n<p>As with many projects, you need to start your email A\/B testing with the end goal in mind. Choose your hypothesis, what you want to learn, or what metric you want to improve.<\/p>\n<img decoding=\"async\" class=\"alignnone size-large wp-image-30861\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2021\/06\/email-metrics-matrix-3-1-672x1024.png\" alt=\"email-centric and business-centric marketing metrics table\" width=\"672\" height=\"1024\" srcset=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2021\/06\/email-metrics-matrix-3-1-672x1024.png 672w, https:\/\/www.litmus.com\/wp-content\/uploads\/2021\/06\/email-metrics-matrix-3-1-197x300.png 197w, https:\/\/www.litmus.com\/wp-content\/uploads\/2021\/06\/email-metrics-matrix-3-1-768x1170.png 768w, https:\/\/www.litmus.com\/wp-content\/uploads\/2021\/06\/email-metrics-matrix-3-1.png 860w\" sizes=\"(max-width: 672px) 100vw, 672px\" \/>\n<p>While you can use email A\/B testing to improve <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/the-pitfalls-of-email-marketing-metrics-ab-testing-video\/\">campaign-level metrics<\/a> like open rates, try to track the impact even further. For example, how does the conversion rate vary from the different emails? Since subject lines set expectations for the content, you might see their influence further than the inbox.<\/p>\n<h3>2. Pick the variable<\/h3>\n<p>Once you know what effect you want to have, it\u2019s time to pick your variable component. Make sure you\u2019re only testing one variable at a time. If there is more than one difference between your control and variable emails, you won\u2019t know what change moved the needle. Isolating your email A\/B tests may feel a bit slower, but you\u2019ll be able to make informed conclusions.<\/p>\n<h3>3. Set up the parameters<\/h3>\n<p>The third step in your email A\/B testing process has the most decisions. When you set up parameters, you decide on all of the pieces that ensure the test is organized. Your decisions include:<\/p>\n<ul>\n<li aria-level=\"1\">How long you\u2019ll run the test. You\u2019ll probably be sitting on the edge of your seat waiting for results, but you need to wait up to a day for results to trickle in.<\/li>\n<li aria-level=\"1\">Who will receive the test. If you want to A\/B test within a particular segment, make sure you have a large enough audience for results to be <a rel=\"noopener\" target=\"_blank\" href=\"https:\/\/www.optimizely.com\/sample-size-calculator\/\">statistically significant<\/a>.<\/li>\n<li aria-level=\"1\">Your testing split. Once you know which segments will receive the test, you have to decide how to split the send. You could do a 50\/50 split where half gets the control, and the other receives the variable version. Or, you can send control version A to 20% and test version B to another 20%, then wait and send the winner to the remaining 60%.<\/li>\n<li aria-level=\"1\">Which metrics you\u2019ll measure. Figure out exactly which metrics you want and how to get the data before your test. How will you define success?<\/li>\n<li aria-level=\"1\">Other confounding variables. Make a note of variables like holidays that could impact the test results but are out of your control.<\/li>\n<\/ul>\n<h3>4. Run the test<\/h3>\n<p>Email A\/B testing is all about options, and that includes how you run the test \u2013 whether for optimizing your <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/what-is-lifecycle-marketing\">lifecycle marketing<\/a> efforts or improving engagement in a single <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/how-to-plan-your-email-campaign-strategy\">email marketing campaign<\/a>. The two main ways to run the test are:<\/p>\n<ul>\n<li aria-level=\"1\">Set up the A\/B test in your ESP to run automatically. Letting your ESP manage the split-sending could be a little easier to manage and is a good option for simple tests (like <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/email-testing-and-qa\">email QA<\/a>) with more surface-level goals like increasing open rates.<\/li>\n<li aria-level=\"1\">Manually split the send. Setting up the two separate emails and manually sending the emails is more hands-on but can give you a cleaner look at data beyond your ESP (like website engagement). Use this method if you want to track results beyond the campaign. If you\u2019re in the middle of an <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/how-to-migrate-esps-easily\">ESP migration<\/a>, this can help with seeing performance and feature gaps.<\/li>\n<\/ul>\n<h3>5. Analyze the results<\/h3>\n<p>Once it\u2019s time to analyze the results, you\u2019ll be grateful for every moment spent carefully planning. Since you went in with a clear idea, you know what to look for once the test is over. Now you need to compare results and share them with your team.<\/p>\n<p>Unless you want to test again. Listen, you don\u2019t have to, but there is a chance that your variable email got a boost from the \u201cshiny new factor.\u201d\u00a0 If you want to confirm the first test results, you can run a similar test (with the same cohort!) to see if the learnings remain true. Then, document those findings and make it official for future campaigns.<\/p>\n\n<div class=\"container pt-3 pb-5 px-1\">\n\t<div class=\"row blog-cta-green rounded-5 p-4\">\n\t\t<div class=\"mx-auto col-12\">\n\t\t\t<div class=\"row d-flex align-items-center\">\n\t\t\t<div class=\"col-lg-6 col-12\">\n\t\t\t\t<p class=\"bold fs-4\">Go beyond opens and clicks<\/p>\n\t\t\t\t<p>Brands that use Litmus Email Analytics see a 43% higher ROI than those that don\u2019t. See what you\u2019re missing. <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/email-analytics\" class=\"bold\">Learn more.<\/a><\/p>\n\t\t\t\t<button class=\"button-blue arrow\"><a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/pricing-litmus\" class=\"text-white text-decoration-none\">Book a demo<\/a><\/button>\n\t\t\t<\/div><!--col-6-->\n\t\t\t<div class=\"col-6 d-none d-lg-block\">\n\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2022\/02\/email-analytics.svg\" width=\"210\" height=\"130\" alt=\"\">\n\t\t\t<\/div><!--col-6-->\n\t\t\t<\/div> <!--row-->\n\t\t<\/div><!--col-12-->\n\t<\/div><!--row-->\n<\/div><!--container-->\n\t\n\t\n\t\n\t\n\n<h2 id=\"elements\">What to A\/B test in your emails<\/h2>\n<p>You can test pretty much everything in your emails, from layout to colors to your copy. \u201cYou may like the look of a white, sleek email, but it may not resonate with your audience because it doesn\u2019t stand out. It\u2019s interesting to test color variations, image variations, whether it\u2019s a rounded or square CTA button, your personalization choices\u2026you never know what can make a difference until you test,\u201d says Espinal. \u201cThese are the tiny changes you can make that contribute to a healthy email marketing ecosystem.\u201d<\/p>\n<p>If you create it, you can test it. To get you started, here are ten common email components to A\/B test:<\/p>\n<h3>1. The inbox envelope: from name, subject line, and preview text<\/h3>\n<p>One of the elements that informs subscribers about an email (from the outside) is the from name. While you can experiment with this if you want, make sure it\u2019s always clear that it\u2019s from your company. Don\u2019t try anything too off-the-wall that could feel spammy. For example, <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/mailchimp\/\">Mailchimp<\/a> uses a few From names including \u201cMailchimp,\u201d \u201cJenn at Mailchimp,\u201d and \u201cMailchimp Research.\u201d<\/p>\n<img decoding=\"async\" class=\"alignnone size-large wp-image-120032\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/inbox-envelope-1024x124.png\" alt=\"Mailchimp subject lines\" width=\"1024\" height=\"124\" srcset=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/inbox-envelope-1024x124.png 1024w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/inbox-envelope-300x36.png 300w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/inbox-envelope-768x93.png 768w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/inbox-envelope-1536x186.png 1536w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/inbox-envelope.png 1600w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\n<p>If you want to increase open rates, the <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/how-to-write-the-perfect-subject-line-infographic\/\">subject line<\/a> is the most common place to start. You can experiment with different styles, lengths, tones, and positioning. For example, <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/use-testing-to-continuously-learn-more-about-your-audience\/\">Emerson A\/B tested two subject lines<\/a> for a free trial email with a white paper:<\/p>\n<ul>\n<li aria-level=\"1\"><strong>Control<\/strong>: Free Trial &amp; Installation: Capture Energy Savings with Automated Steam Trap Monitoring<\/li>\n<li aria-level=\"1\"><strong>Variable<\/strong>: [White Paper] The Impact of Failed Steam Traps on Process Plants<\/li>\n<\/ul>\n<p>That particular test revealed a 23% higher open rate for the subject line referencing the white paper.<\/p>\n<p>While the subject line arguably leads the charge in enticing a subscriber to open an email, it isn\u2019t the only option you have. Testing your preheader or preview text can also boost open rates.<\/p>\n<h3>2. HTML vs. plain text<\/h3>\n<p>If you mostly send either HTML or plain text emails, it might be worth seeing if the grass is greener on the other side. Here at Litmus, we <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/the-results-are-in-a-b-testing-html-vs-plain-text-emails\/\">A\/B tested these two email styles<\/a> across a few segments. Through a few tests, we found that the best messaging varies between customers and non-customers and that plain text emails have a firm place in our email lineup.<\/p>\n<p><strong>HTML:<\/strong><\/p>\n<div class=\"image-scroll mb-3\"><img decoding=\"async\" class=\"alignnone\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/HTML-email.png\" alt=\"\" \/><\/div>\n\n<p><strong>Pain text:<\/strong><\/p>\n<div class=\"image-scroll mb-3\"><img decoding=\"async\" class=\"alignnone\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/plain-text-email.png\" alt=\"\" \/><\/div>\n\n<h3>3. Personalization<\/h3>\n<p>\u201cFirst name\u201d is only one kind of personalization you can choose for your emails. While this method can increase clicks, you can expand your personalization horizons for your A\/B tests, including dynamic content, interactive elements, or by adding (or removing) copy about a person\u2019s location, previous purchases, customer status, and more.<\/p>\n<figure id=\"attachment_117919\" aria-describedby=\"caption-attachment-117919\" style=\"width: 1024px\" class=\"wp-caption alignnone\"><img decoding=\"async\" class=\"wp-image-117919 size-large\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/06\/03_PersonalizationStrategie-1024x599.jpeg\" alt=\"Pie chart from Litmus' State of Email report showing which personalization strategies marketers find most effective: segmentation (most), dynamic content, personalized subject lines, location-based personalization, and behavior-based triggers (least).\" width=\"1024\" height=\"599\" srcset=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/06\/03_PersonalizationStrategie-1024x599.jpeg 1024w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/06\/03_PersonalizationStrategie-300x176.jpeg 300w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/06\/03_PersonalizationStrategie-768x450.jpeg 768w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/06\/03_PersonalizationStrategie.jpeg 1500w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption id=\"caption-attachment-117919\" class=\"wp-caption-text\">Source: <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/state-of-email-reports\">State of Email Report 2025<\/a><\/figcaption><\/figure>\n<p>&nbsp;<\/p>\n<p>When we asked email marketers for the <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/state-of-email-reports\">2025 State of Email Report <\/a>what moved the needle the most with their personalization, dynamic content came in on top, just after your segmentation strategy. If you\u2019re not sold on dynamic content yet, test it.<\/p>\n<p>Espinal likes to test personalization more than any other element because it has the biggest upside potential. \u201cOne of the most exciting tests I ran at my previous company was a specific nurture for a product by different audience buckets,\u201d she says. \u201cWe changed the body copy of the email and ran A\/B tests against a control for our three segments. It\u2019s extra work but can make a product launch that much more successful.\u201d<\/p>\n<h3>4. Automation and timing<\/h3>\n<p>Most email A\/B testing focuses on what goes in an email, but you can also test when to send it.<\/p>\n<p>For example, you could adjust how long after a person abandons their cart before you send them a reminder. Another A\/B testing method to try is how many emails in a triggered sequence you send.<\/p>\n<p>That\u2019s true for testing broadcast emails, but automated and transactional emails deserve testing and improvement, too. Often, these emails are the ones doing the heavy lifting of subscriber engagement, so it\u2019s crucial to test these always-on emails.<\/p>\n<h3>5. Copy, imagery, and design choices<\/h3>\n<p>The tone and positioning of your email copy impact whether the message catches a reader\u2019s interest or not. A\/B testing in the \u201ccopy\u201d category covers a ton of elements in your email, including body copy, headlines, and button copy.<\/p>\n<p>In addition to the design of an email, you can play around with the length of the message. Here are a few questions to ask yourself:<\/p>\n<ul>\n<li aria-level=\"1\">Do subscribers want more content and context in the message, or just enough to pique their interest?<\/li>\n<li aria-level=\"1\">What length is ideal for different types of email? Or different devices?<\/li>\n<li aria-level=\"1\">Do all segments prefer the same length of email?<\/li>\n<\/ul>\n<p>If you use stylized emails, try A\/B testing your visuals. Do different hero images change engagement? Can you use <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/a-guide-to-animated-gifs-in-email\/\">animated GIFs<\/a> in longer emails to increase <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/email-attention-spans-increasing-infographic\/\">read time<\/a>? Does including an infographic in an email make people more likely to forward it? The possibilities are nearly endless.<\/p>\n<table class=\"table table-striped\">\n<thead>\n<tr>\n<th>A\/B Testing Element<\/th>\n<th>Why Test It?<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>From name, subject line, preview text<\/td>\n<td>Changing one of these elements can impact your open rate. And we all know that you don\u2019t get any clicks without opens.<\/td>\n<\/tr>\n<tr>\n<td>HTML vs. Plain text<\/td>\n<td>Get a sense of the tone and style of your email designs that resonate the most with your subscribers.<\/td>\n<\/tr>\n<tr>\n<td>Personalization<\/td>\n<td>Play around with how much to personalize your emails and which elements to personalize, like first name, geolocation, customer status, and dynamic product recommendations.<\/td>\n<\/tr>\n<tr>\n<td>Automation and timing<\/td>\n<td>Not just what you send but when you send it can impact opens and clicks. This goes for your automated and transactional emails, too.<\/td>\n<\/tr>\n<tr>\n<td>Copy, imagery, and design<\/td>\n<td>There are endless ways to find optimization wins with your design and copy by changing out headlines, body copy, CTA buttons, and more.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2 id=\"not-test\">When NOT to run an email marketing A\/B test<\/h2>\n<p>There\u2019s plenty of elements you can A\/B test\u2026but don\u2019t confuse testing for taking action.<\/p>\n<p>Espinal says, \u201cAnytime you need to send a critical communication, or something very time-sensitive, that\u2019s not the time to run a test. That includes transactional emails, like a confirmation email or shipping confirmation. Put your energy elsewhere.\u201d<\/p>\n<p>The most important thing to keep in mind? That whatever test you run can be repeated. So if you\u2019re thinking of doing an A\/B test on a random, ad hoc email campaign because you read this article and think you \u201cshould,\u201d don\u2019t worry! You don\u2019t have to test every single campaign that you run. \u201cIt\u2019s all about taking that data and replicating that moving forward, so if there\u2019s any part of the campaign that you just can\u2019t do that with, save the A\/B test for another time,\u201d adds Espinal.<\/p>\n<div class=\"container pt-3 pb-5 px-1\">\n<div class=\"row blog-cta-green rounded-5 p-4\">\n<div class=\"mx-auto col-12\">\n<div class=\"row d-flex align-items-center\">\n<div class=\"col-12 text-center\">\n<p class=\"bold fs-4\">Enterprise email, simplified<\/p>\n<p>Power your enterprise email strategy with advanced testing, automation, and security to scale effortlessly.Learn more.<\/p>\n<p><button class=\"button-blue arrow\"><a class=\"text-white text-decoration-none\" rel=\"noopener\" href=\"https:\/\/www.litmus.com\/enterprise\">Scale your email strategy<\/a><\/button><\/p>\n<\/div>\n<div class=\"d-none\"><img decoding=\"async\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2022\/02\/email-analytics.svg\" alt=\"\" width=\"210\" height=\"130\" \/><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<h2 id=\"enterprise\">Mastering enterprise A\/B testing<\/h2>\n<p><span style=\"font-weight: 400;\">A\/B testing a few hundred emails feels easy\u2014as easy as picking three or four subject lines, hitting send, and waiting for the winner to emerge. However, when you&#8217;re managing enterprise email A\/B tests and sending millions, it&#8217;s a whole different ballgame. One wrong move can derail your efforts, and determining what works becomes significantly more complicated.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">While the goal of any experiment is to find variants that work best for your marketing, email testing at scale demands thoughtful, enterprise-grade strategies.<\/span><\/p>\n<h3>The realities of enterprise A\/B testing<\/h3>\n<p><span style=\"font-weight: 400;\">To successfully execute enterprise A\/B testing, teams must overcome challenges that smaller campaigns simply do not encounter:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Data volume and quality.<\/b><span style=\"font-weight: 400;\"> Using massive datasets makes it easy to misinterpret results, focus on the wrong metrics, or fall victim to analysis paralysis. Furthermore, a tiny tracking or randomization error can completely compromise your data quality.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>The paradox of scale.<\/b><span style=\"font-weight: 400;\"> When email testing at scale, you might notice data outcomes that look like big wins but are actually meaningless overall. Conversely, massive datasets can mask segment differences, hiding huge wins within minority audiences.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Technical and tool limitations.<\/b><span style=\"font-weight: 400;\"> Setting up and tracking tests for smaller lists is straightforward. At an enterprise level, you need a reliable system that smoothly handles clean randomization, deep analytics, and rapid automated deployment once you&#8217;ve found a winner.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">By shifting from basic tools to specialized software designed for large-scale experimentation, you can cut through the noise, avoid costly false positives, and find the true potential of your large email lists.<\/span><\/p>\n<h2 id=\"brands\">How top brands use email A\/B testing to drive results<\/h2>\n<p>What does A\/B testing look like in action? Here\u2019s how top brands use it in their regular email marketing cadence, as told to our email geeks at Litmus Live a few years back:<\/p>\n<h3>1. Square does incremental testing to isolate their experiments<\/h3>\n<p>Tyler Michael, from Square, uses A\/B testing incrementally, changing one aspect of their nurture sequences and newsletters at a time so they can isolate exactly what worked or what didn\u2019t. He recommends traditional elements to test, but he often focuses on <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/how-the-worlds-best-email-brands-run-a-b-tests\/\">timing dimensions you can A\/B test<\/a> like:<\/p>\n<ul>\n<li aria-level=\"1\">Sending delay<\/li>\n<li aria-level=\"1\">Timezone localization<\/li>\n<li aria-level=\"1\">Day of the week<\/li>\n<\/ul>\n<p>\u201cIf you\u2019re ever surprised by the results, run the test again,\u201d he advises. \u201cThere are several elements that can impact the validity of your results, like seasonality (holiday vs. summer), execution (load times or errors), or timing (day of week). The longer you run an experiment, the more likely your significance will stabilize.\u201d<\/p>\n<div class=\"my-3\">\n<p><script src=\"https:\/\/fast.wistia.com\/embed\/medias\/bd39fb43h0.jsonp\" async><\/script><script src=\"https:\/\/fast.wistia.com\/assets\/external\/E-v1.js\" async><\/script><\/p>\n<div class=\"wistia_responsive_padding\" style=\"padding: 39.17% 0 0 0; position: relative;\">\n<div class=\"wistia_responsive_wrapper\" style=\"height: 100%; left: 0; position: absolute; top: 0; width: 100%;\">\n<div class=\"wistia_embed wistia_async_bd39fb43h0 videoFoam=true\" style=\"height: 100%; position: relative; width: 100%;\">\n<div class=\"wistia_swatch\" style=\"height: 100%; left: 0; opacity: 0; overflow: hidden; position: absolute; top: 0; transition: opacity 200ms; width: 100%;\"><img decoding=\"async\" style=\"filter: blur(5px); height: 100%; object-fit: contain; width: 100%;\" src=\"https:\/\/fast.wistia.com\/embed\/medias\/bd39fb43h0\/swatch\" alt=\"\" aria-hidden=\"true\" \/><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<h3>2. Intuit built a rapid email experimentation framework<\/h3>\n<p>Rian Lemmer and Kate Tinkleburg from Intuit recommend failing fast and savoring the surprises as much as possible for their email marketing program. \u201cWe\u2019re talking about moving a couple of hours from idea to experiment in the \u2018doing\u2019 phase as fast as possible. Sometimes we even set aside our regular jobs to take a couple of days just doing experiments so we can iterate more quickly and build momentum,\u201d says Lemmer.<\/p>\n<div class=\"my-3\">\n<p><script src=\"https:\/\/fast.wistia.com\/embed\/medias\/5qb9y45w01.jsonp\" async><\/script><script src=\"https:\/\/fast.wistia.com\/assets\/external\/E-v1.js\" async><\/script><\/p>\n<div class=\"wistia_responsive_padding\" style=\"padding: 39.38% 0 0 0; position: relative;\">\n<div class=\"wistia_responsive_wrapper\" style=\"height: 100%; left: 0; position: absolute; top: 0; width: 100%;\">\n<div class=\"wistia_embed wistia_async_5qb9y45w01 videoFoam=true\" style=\"height: 100%; position: relative; width: 100%;\">\n<div class=\"wistia_swatch\" style=\"height: 100%; left: 0; opacity: 0; overflow: hidden; position: absolute; top: 0; transition: opacity 200ms; width: 100%;\"><img decoding=\"async\" style=\"filter: blur(5px); height: 100%; object-fit: contain; width: 100%;\" src=\"https:\/\/fast.wistia.com\/embed\/medias\/5qb9y45w01\/swatch\" alt=\"\" aria-hidden=\"true\" \/><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p>\u201cMost importantly, it needs to have real metrics behind it,\u201d adds Tinkleburg. Surveys take too much time and introduce bias, which is why A\/B testing allows them to get from A to Z faster. \u201cYou need to be able to see their behavior and make changes based on that. With email we have plenty of metrics you can use, but you need real customer currency so they have skin in the game or willingness to pay for the experiment to be worthwhile,\u201d she says.<\/p>\n<h3>3. Indeed takes A\/B testing further down the funnel<\/h3>\n<p>Lindsay Brothers, a product manager at Indeed, believes that experimentation is the best way to learn. \u201cWe\u2019re often wrong,\u201d says Brothers. \u201cJob alerts, our most popular email list, hadn\u2019t been tested for years. We tested the copy for the CTA of our form and absolutely no one thought the winner would win. More importantly, every single one did better than the control. We only stood to gain by testing this!\u201d<\/p>\n<div class=\"my-3\">\n<p><script src=\"https:\/\/fast.wistia.com\/embed\/medias\/q56roezvfp.jsonp\" async><\/script><script src=\"https:\/\/fast.wistia.com\/assets\/external\/E-v1.js\" async><\/script><\/p>\n<div class=\"wistia_responsive_padding\" style=\"padding: 39.38% 0 0 0; position: relative;\">\n<div class=\"wistia_responsive_wrapper\" style=\"height: 100%; left: 0; position: absolute; top: 0; width: 100%;\">\n<div class=\"wistia_embed wistia_async_q56roezvfp videoFoam=true\" style=\"height: 100%; position: relative; width: 100%;\">\n<div class=\"wistia_swatch\" style=\"height: 100%; left: 0; opacity: 0; overflow: hidden; position: absolute; top: 0; transition: opacity 200ms; width: 100%;\"><img decoding=\"async\" style=\"filter: blur(5px); height: 100%; object-fit: contain; width: 100%;\" src=\"https:\/\/fast.wistia.com\/embed\/medias\/q56roezvfp\/swatch\" alt=\"\" aria-hidden=\"true\" \/><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p>You\u2019d think it would be something like \u201csubscribe,\u201d or \u201csign up,\u201d for their CTA to be as clear as possible, but the winner was \u201cactivate.\u201d They increased their email signups by testing the form by 12%\u2014a huge win over time, and the beginning of A\/B testing other aspects of their email marketing program beyond what\u2019s in the email itself.<\/p>\n<p style=\"padding-left: 15px; border-left: 10px solid #0d5477;\"><strong>Check out <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/how-the-worlds-best-email-brands-run-a-b-tests\" target=\"_blank\" rel=\"noopener\">the full story here \u2192<\/a><\/strong><\/p>\n<p><span style=\"font-weight: 400;\">\n<div class=\"container pt-3 pb-5\">\n\t<div class=\"row blog-cta-blue rounded-5 p-4\">\n\t\t<div class=\"col-12 mx-auto\">\n\t\t\t<div class=\"row d-flex align-items-center\">\n\t\t\t<div class=\"col-lg-6 col-12\">\n\t\t\t\t<p class=\"bold fs-4\">Learn from the best<\/p>\n\t\t\t\t<p>Your favorite brands use Litmus to deliver flawless email experiences. Discover the ROI your emails can achieve with Litmus.<\/p>\n\t\t\t\t<button class=\"button-blue arrow\"><a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/customers\" class=\"text-white text-decoration-none\">Explore Case Studies<\/a><\/button>\n\t\t\t<\/div><!--col-6-->\n\t\t\t<div class=\"col-6 d-none d-lg-block\">\n\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2024\/12\/blog-cta-12172024.svg\" width=\"208\" height=\"171\" alt=\"\">\n\t\t\t<\/div><!--col-6-->\n\t\t\t<\/div> <!--row-->\n\t\t<\/div><!--col-12-->\n\t<\/div><!--row-->\n<\/div><!--container-->\n\t\n\t\t\n\t\n\t\n\t\n<\/span><\/p>\n<h2 id=\"popular-tools\">Popular email marketing A\/B testing platforms<\/h2>\n<p>You can find A\/B testing in pretty much any ESP these days, though the additional features will vary. For example, at Litmus we\u00a0use Marketing Cloud Account Engagement (formally Pardot). Here\u2019s what our setup looks like when we run an A\/B test:<\/p>\n<img decoding=\"async\" class=\"alignnone wp-image-120044 size-full\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/Pardot-AB-testing-.png\" alt=\"Setting up an A\/B test in Marketing Cloud Account Management \" width=\"512\" height=\"292\" srcset=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/Pardot-AB-testing-.png 512w, https:\/\/www.litmus.com\/wp-content\/uploads\/2025\/09\/Pardot-AB-testing--300x171.png 300w\" sizes=\"(max-width: 512px) 100vw, 512px\" \/>\n<p>When you\u2019re comparing different A\/B testing options within your ESP, consider:<\/p>\n<ol>\n<li aria-level=\"1\">Does it allow you to randomize the audience? This is key for making sure you get a statistically significant result.<\/li>\n<li aria-level=\"1\">How easy it is to create two versions of the same email to send at the same time, especially if you\u2019re doing something more complex than subject line tests.<\/li>\n<li aria-level=\"1\">Whether you can turn off send time optimization so you\u2019re eliminating as many timing factors as possible\u2014unless, of course, you\u2019re testing timing.<\/li>\n<li aria-level=\"1\">How the ESP packages up the \u201cwinner\u201d variant with additional insights, or if it uses AI to speed up the A\/B testing process.<\/li>\n<li aria-level=\"1\">Integrations the platform has with other analytics tools, like Litmus Analytics, so you can combine your pre-send testing with your A\/B testing to optimize your email marketing program even further.<\/li>\n<\/ol>\n<p>Whether you use HubSpot, Constant Contact, Salesforce Marketing Cloud, or something else, check to see what kind of A\/B testing features are available in your ESP. If you\u2019re not happy with what your ESP has to offer, a tool like Optimizely, Hotjar, or Crazy Egg can help you. Though originally designed for landing pages, they have some features you can use\u2014like a probability calculator\u2014to run your A\/B tests on email campaigns.<\/p>\n<h2 id=\"before-launch\">Steps before you launch your first email A\/B test<\/h2>\n<p>Before you start your first A\/B test, here\u2019s a summary of everything you need to know about email A\/B testing:<\/p>\n<table class=\"table table-striped\">\n<thead>\n<tr>\n<th>Step<\/th>\n<th>Why?<\/th>\n<th>For example\u2026<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Choose an objective and make a hypothesis.<\/td>\n<td>You should only test one element of your email at a time, and measure it against the appropriate metrics.<\/td>\n<td>Subject lines \/ open rates<\/td>\n<\/tr>\n<tr>\n<td>Randomize your audience and choose a large enough sample size.<\/td>\n<td>You need to achieve statistical significance and probability confidence (p&lt;0.05) to declare a \u201cwinner.\u201d<\/td>\n<td>10,000 or more audience members, random slice<\/td>\n<\/tr>\n<tr>\n<td>Run the test.<\/td>\n<td>This will help you make adjustments to future campaigns. Be sure to choose a campaign you can replicate.<\/td>\n<td>Variant A: CTA button color (default, what you always do)<\/p>\n<p>Variant B: CTA button color (new)<\/td>\n<\/tr>\n<tr>\n<td>Analyze the results, document your findings, and roll out changes to a future campaign.<\/td>\n<td>The value in A\/B testing comes from choosing a winner and moving forward with those insights.<\/td>\n<td>Example: Variant B (new CTA color) won. The next email has the new CTA color.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2 id=\"litmus\">Take the guesswork out of email testing with Litmus<\/h2>\n<p>All ESPs give you access to the same standard email metrics, and you can also tap into things, like web analytics, to understand behavior outside of the inbox. If you want to dig deeper into your A\/B tests with advanced metrics, Litmus can help you do more pre-send testing, including <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/blog\/6-crucial-email-qa-tasks-you-can-automate-with-litmus\">email QA tests<\/a>.<\/p>\n<p>Here are just a few use cases where <a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/email-analytics\/\">Litmus Email Analytics<\/a> could improve your insights:<\/p>\n<ul>\n<li aria-level=\"1\">Compare the read rates between variations, not just open rates, to see which subject line version attracted the most engaged subscribers.<\/li>\n<li aria-level=\"1\">Understand which content leads to the highest share rate so you can leverage learnings to grow your referral program.<\/li>\n<li aria-level=\"1\">Analyze A\/B test results between email clients and devices, particularly if what you\u2019re testing doesn\u2019t have broad email client support.<\/li>\n<\/ul>\n<p>Once you have your advanced analytics reports and findings, Litmus makes it easy to share the results with your team. Then, you can optimize and drive strategies in email and the rest of your marketing channel mix.<\/p>\n\n<div class=\"container pt-3 pb-5 px-1\">\n\t<div class=\"row blog-cta-green rounded-5 p-4\">\n\t\t<div class=\"mx-auto col-12\">\n\t\t\t<div class=\"row d-flex align-items-center\">\n\t\t\t<div class=\"col-lg-6 col-12\">\n\t\t\t\t<p class=\"bold fs-4\">Send with total confidence<\/p>\n\t\t\t\t<p>Preview emails in 100+ clients, catch errors, and ensure accessibility. Cut QA time in half.<\/p>\n\t\t\t\t<button class=\"button-blue arrow\"><a rel=\"noopener\" href=\"https:\/\/www.litmus.com\/email-testing\" class=\"text-white text-decoration-none\">Start email testing<\/a><\/button>\n\t\t\t<\/div><!--col-6-->\n\t\t\t<div class=\"col-6 d-none d-lg-block\">\n\t\t\t\t<img decoding=\"async\" src=\"https:\/\/www.litmus.com\/wp-content\/uploads\/2024\/07\/blog-cta-email-guardian-07292024.svg\" width=\"210\" height=\"180\" alt=\"\">\n\t\t\t<\/div><!--col-6-->\n\t\t\t<\/div> <!--row-->\n\t\t<\/div><!--col-12-->\n\t<\/div><!--row-->\n<\/div><!--container-->\n\t\n\t\n\t\n\t\n\n  \t\t\t<\/div>\n  \t\t<\/div>\n  \t<\/div>\n  <\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Learn how to run and optimize email A\/B tests with confidence. Litmus tools, enterprise insights, and real-world tips all in one guide.<\/p>\n","protected":false},"author":25,"featured_media":30846,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"tags":[102,10254,65,10246,9805],"blog_category":[53],"class_list":["post-30844","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","tag-html","tag-preview","tag-subject-lines","tag-testing","tag-text","blog_category-tips-resources"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.5 (Yoast SEO v27.7) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>How to Run A\/B Tests on Your Emails - Litmus<\/title>\n<meta name=\"description\" content=\"Learn how to run and optimize email A\/B tests with confidence. 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