Free A/B testing tool

Did your test actually win?

Enter your visitors and conversions for each version. Zyro tells you the confidence level and whether the result is real, or just random noise.

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Control (Original)
Variation B
What this tells you

A winning-looking number is often just luck.

Statistical significance is the probability that the gap in conversion rates between your Control and Variation is not down to random chance. The industry standard is 95% confidence, meaning only a 5% chance the result is a false positive.

Human intuition is poor at probability. A variation can look like it is winning, for example 50 conversions against 40, when mathematically that difference could easily happen by luck. This calculator does the maths so you decide on evidence, not a hunch. The default numbers are illustrative, swap in your own.

How to use it

Three numbers in, one answer out.

Enter the visitors and conversions for your original, then the same for your variation. The confidence level updates the moment you type, and the verdict flips to Significant once you cross the 95% threshold. No formulas to remember, no spreadsheet to build.

Common questions

Significance, in plain English.

What is statistical significance?

Statistical significance is the probability that the difference in conversion rates between your variations is not due to random chance. A standard threshold is 95% confidence.

Why use a significance calculator?

Human intuition is poor at probability. A variation can look like it is winning when the gap could easily happen by luck. A calculator does the maths so you decide on evidence, not a hunch.

Keep going

Stop calculating by hand. Let Zyro run it.

Zyro splits your traffic, tracks conversions in real time, and tells you the winner in plain English, in dollars, the moment the result holds up.

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