A/B Test Calculator

    Sample size. Test duration. Just the facts.

    Plan your A/B test: the sample size per variant and how long to run it to detect a target uplift at 95% confidence and 80% power.

    Statistical Rigor

    Classical power analysis based on means and coefficient of variation. No guesswork, just math.

    Instant Results

    Get the sample size per variant and the test duration instantly - in milliseconds, no spreadsheets.

    Clear Guidance

    Know exactly how many users you need per variant and how long to run the test. Like consulting a growth analyst.

    Built For Teams That Ship Fast

    Designed for founders, marketers, and product teams who need answers, not spreadsheets

    ✓ Solo Founders

    Validate marketing experiments without hiring a data analyst

    ✓ Growth Marketers

    Test copy, ads, and landing pages with statistical confidence

    ✓ Product Teams

    Analyze feature rollouts and UX changes with precision

    ✓ E-commerce Shops

    Optimize checkout flows and product pages for maximum revenue

    Ready to Plan Your Test?

    Get your sample size per variant and test duration in seconds