Free A/B Testing & Marketing Calculators
Rigorous, free calculators for the decisions growth teams get wrong most often: whether a test result is real, how long to run it, when it is safe to stop, whether the experiment itself is broken, and what your ads must return to make money. No sign-up.
- A/B Test Significance Calculator: Is your result real? p-value, lift and confidence interval from visitors and conversions.
- A/B Test Sample Size Calculator: Visitors per variant and test duration, before you launch.
- Can I Stop My A/B Test Yet?: Stop peeking. Find out if your test can end, and what your peeking has cost.
- Sample Ratio Mismatch (SRM) Checker: Is your traffic split broken? A chi-square test that catches invalid experiments.
- Break-Even ROAS & Target CPA Calculator: The ROAS and CPA your ads must hit to make money, from your real unit economics.