Free A/B testing tools.
Two small calculators for the two questions every A/B test raises. No account, and they run in your browser: what you type into them is never sent anywhere.
A/B test significance calculator
Is your result real, or luck? Enter visitors and conversions for two versions and get a plain verdict, the p-value, lift and 95% ranges.
Open the calculatorA/B test sample size calculator
How many visitors does your test need, how long will it take, and what can your traffic detect? Plan the test before you start it.
Open the calculatorKeep the test next to the rest of your work.
Cleo keeps A/B tests in its Testing tab alongside the clients, tasks and dates they come from: numbers from your site or logged by the day, a target number of visitors, and a verdict in plain words. Free to start, no card.