A/B testing

Stop guessing which subject line wins. Test it and let the data decide.

Write two versions of your subject line or content, send them side by side, and Mailsoftly tracks the opens and clicks for each one and points you to the winner. Better emails without the guesswork, right inside the tool you already send from.
Free to start with your Google Workspace or Microsoft 365 account · No credit card required
Mailsoftly A/B test result showing the winning subject line variant marked with a trophy and its open and click lift over the other version
Mailsoftly A/B test in progress comparing the live open rates of variant A and variant B
Mailsoftly A/B test setup where you write variant A and variant B of the subject line before sending
Subject line test · Winner decided
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What is A/B testing

Two versions, one clear winner

A/B testing, also called split testing, is when you send two versions of the same email, an A and a B, to see which one performs better. You change one thing, usually the subject line, and let real opens and clicks tell you which version your audience prefers. In Mailsoftly you set both variants, send them, and read the result on one screen.
Test what moves the needleTry two subject lines to lift opens, or two versions of the content to lift clicks. Change one element at a time so the result is easy to trust.
Judged by real behaviorMailsoftly counts the opens and clicks each variant earns from your own contacts, not a guess or a preview. The numbers come from real sends.
The winner is obviousWhen the test settles, the stronger version is marked as the winner with its lift over the other, so you know what to send more of next time.
Mailsoftly A/B test setup screen where you write variant A and variant B of the subject line for a campaign
How a test runs

Set it, send it, and see which one wins

A/B testing is one part of the Mailsoftly platform, next to your reporting and automation tools. Here is the full loop, from first draft to decided winner.
✎ Write the variants

Two takes on one idea

Draft variant A and variant B in the setup. Keep everything else the same and change one thing, so you learn exactly what made the difference.

Mailsoftly A/B test setup with variant A and variant B subject lines ready to send
📈 Watch it run

Live opens and clicks

Once the test sends, Mailsoftly tracks how each variant is doing in real time. You can watch the open and click rates for A and B move as your contacts respond.

Mailsoftly A/B test running with live open and click rates compared between variant A and variant B
🏆 Pick the winner

Send more of what works

When the result is in, the winning variant is called out with its lift. Use what you learned in your next campaign, your automations and your everyday sends.

Mailsoftly A/B test winner marked with a trophy and the open and click lift over the losing variant
Why it matters

Small tests, better emails over time

The subject line decides whether your email gets opened at all, and the content decides whether people click. Testing both, one change at a time, turns hunches into a habit of sending what your audience actually responds to. Pair it with personalization and a well timed email blast and every send builds on the last.
Mailsoftly A/B test in progress showing the live open and click comparison between two subject line variants

One subject line test. A clear winner. No spreadsheet.

Here is a real subject line A/B test inside Mailsoftly: two variants sent, opens and clicks measured, and the stronger version marked as the winner with its lift.
2
variants tested
A/B
opens and clicks compared
1
clear winner
Mailsoftly A/B test result with the winning subject line variant highlighted and its open and click lift shown
FAQ

A/B testing, answered

What is A/B testing in email marketing?

A/B testing, also called split testing, is sending two versions of an email, an A and a B, to find out which one performs better. You change one element, usually the subject line, and let real opens and clicks show which version your audience prefers. In Mailsoftly you set both variants, send them, and see the winner on one screen.

What should I A/B test first?

Start with the subject line, because it decides whether your email gets opened at all. Once you are comfortable, test the content to see which version earns more clicks. Change one thing at a time so you can trust what caused the difference.

How does Mailsoftly pick the winner?

Mailsoftly measures the opens and clicks each variant earns from your own contacts, then marks the stronger version as the winner with its lift over the other. The result comes from real sends to real people, not a preview or a guess.

How many contacts do I need to run an A/B test?

You can test with the list you have. Larger lists give a clearer result faster because more opens and clicks make the difference between the two variants easier to read, but even a modest list will point you toward the stronger version over a few sends.

Is A/B testing free to use?

You can start free with your Google or Microsoft account and use Mailsoftly on the free plan, no credit card required. Google Workspace and Microsoft 365 accounts get the quickest start; personal Gmail or Outlook.com works too, with lower sending limits while your account builds trust. Paid plans add higher sending volumes.

What can I do with the results of a test?

Use the winning variant in your next campaign, carry the lesson into your automated sequences, and keep testing one change at a time. Over several sends, small wins on subject lines and content add up to emails that consistently get opened and clicked.

Test your next subject line tonight

Sign up free with your Google Workspace or Microsoft 365 account, write two subject lines, and let real opens and clicks tell you which one to send.

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