Request a callHow long will your A/B test take?
Enter your baseline conversion rate, the smallest lift worth detecting and weekly traffic to the page. The calculator returns the visitors needed per version and the test duration, and tells you whether the page has enough traffic for a clean test or whether to fix funnel structure first.
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A 20% relative lift moves a 3% rate to 3.6%.
Bolder changes need far less traffic. The dashed line marks a 6-week practical limit.
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How it works
Baseline and target
Your current conversion rate and the variant rate you want to detect, from the relative lift.
Sample size per version
A two-proportion test at your chosen confidence and power, the standard used by VWO and Optimizely.
Duration
Visitors per version times the number of versions, divided by weekly traffic to the page.
The decision
Under five weeks fits one cycle. Longer means testing a bolder change or a higher-traffic page.
How much traffic do you need for A/B testing in B2B?
A few thousand visitors per month on the tested page is usually the floor. Below that, tests take months to reach significance, so we fix funnel structure, forms and demo flow first.
What minimum detectable effect should I use?
Use the smallest lift that would change a business decision. Most B2B pages should test bold changes worth 15% to 30% relative lift, because small tweaks need traffic most B2B sites do not have.
Should I stop a test as soon as it looks significant?
No. Peeking and stopping early inflates false positives. Decide the sample size up front, run full weeks to cover weekday patterns, and then read the result.
Which metric should a B2B test optimize?
Qualified demos or sales-accepted leads, not raw form fills. We check every winner against sales acceptance in the CRM before rolling it out.
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