Tool

A/B Test Statistical Significance Calculator

VWO Free Beginner

When one ad beats another, this free calculator tells you whether the gap is real or just luck. You plug in visitors and conversions for each version and it returns the probability that the difference holds up, no spreadsheet or stats background needed. Use it as a gut check before you shift budget onto the ad that only looks like the winner.

  • Enter visitors and conversions for control and variant, and it reports the chance the difference is genuine rather than noise.
  • A small lead on small numbers usually comes back as not significant, which is the honest answer you want before spending more.
  • It is free and needs no signup, so you can sanity-check every head-to-head test as you run it.
Open on wingify.com ↗

The question it answers

  1. What's the minimum data I need before I trust that a paid campaign is actually working?

Read with it

  1. Most founders call a paid campaign a winner or loser off a handful of clicks, and this piece walks through exactly why that... GuessTheTest Article Calculating Sample Size in A/B Testing: Everything You Need to Know Deborah O'Malley
  2. Video Facebook Ads Learning Phase Explained Hernan Vazquez
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