About A/B Tests

A/B tests compare different versions of a single email to see how small changes can have an impact on your results. Choose what you want to test, like the subject line or content, and compare results to find out what works and what doesn't work for your audience.

In this article, you'll learn about A/B tests.

Things to know

• Depending on your plan, you may not have access to A/B tests. To find out what features are included in each plan, check out our pricing page.
• Create a Multivariate test to test and compare multiple variables in a single campaign. This feature is included with the Standard plan or higher.

Definitions

When we talk about A/B tests, we use some terminology that's a little different from how we talk about other tools and tasks in Mailchimp.

Variable
The element of your test that you want to compare. With an A/B test, you can test 1 of 4 variables: subject line, From name, content, and send time. Each version of the variable is called a variation.

Combination
Each variation of your test that is created from your chosen variables. If you want to test 3 different From names, we'll create 3 different combinations of your campaign. Combinations sent in the test phase are called test combinations.

Test phase
The period of time after the combinations are sent out and we compare the results. Data collected during the test phase can be used to determine the test's winning combination automatically or manually.

Winner or winning combination
The combination that performs the best. This may be automatically determined by click rate, open rate, or total revenue, or manually chosen based on the reporting data you find the most valuable.

How A/B tests work

Set up the A/B test

You'll choose a single variable type—subject line, From name, content, or send time—and create up to 3 variations. We'll generate all possible combinations and send them to different sets of recipients, so no one receives more than 1 combination of your email.

The combination that recipients receive are chosen at random and tracked solely for the purpose of choosing a winner, so you won't be able to see which combination went to a specific person.

Choose winner criteria

Send the combinations to all your recipients at once if you have a small audience or segment, or if you're testing send time. With other variables or a large audience or segment, send your test combinations to a percentage of your recipients, and send the winning combination to your remaining recipients.

To choose the winner, use 1 of these options.

• Automatic: open rate, click rate, or total revenue
  Use these options to send the winning combination to your remaining recipients after a set amount of time. The winner can be determined by the highest open or click rate, or total revenue if your online store is connected to your account.

• Manual: report statistics
  Use this option to choose a winner yourself based on reporting data or other factors that you find to be the most valuable.

Variables you can test

• Subject line
  Try different phrasing or sales offers to see what gets the most attention.

• From name
  See if your recipients are more responsive to emails coming from a person's name or from the name of your company or organization. You'll provide the From name and From email address you want to use for each combination.

• Content
  Create different versions of your content to see what gets a better response. Use this variable to test small content changes or completely different templates. When you test content, you may want to better understand the efficacy of calls to action, links, or buttons. Use our link comparison tool in the campaign report to see how your links performed in each combination.

• Send time
  Learn when your recipients are most likely to open your emails. Since this option tests specific days and times, you must send your combinations to all your recipients at once because the winning combination can't send at a time that has already passed. Instead, use this data to inform when to send or schedule future emails.

A/B test ideas

Here are some common ways Mailchimp users learn from A/B tests.

• What day of the week gets better open rates?
• Does a subject line with an incentive or a teaser work best?
• Does including your company name in your subject line increase engagement?
• Is it better to use your name as the from name, or your company's name?
• Does the time of day an email is sent affect the click rate?
• Are recipients more likely to click a linked image or linked text?
• Do recipients prefer an email that contains a GIF or one with static images?