The level of certainty that the A/B test results you’ve achieve are reliable and repeatable.

On GuessTheTest, we aim to publish only tests that have achieved 95% confidence or above.

A 95% confidence level means there’s just a 5% chance the results are due to random factors — and not the variables that changed within the A/B test.

Note, it’s impossible to reach 100% confidence. You can only ever achieve 99.99% confidence.