A/B Test Duration Calculator
Estimate how long you should run your A/B tests based on your current traffic, desired confidence level, and expected improvement.
Estimated Test Duration
Enter your parameters and click Calculate to see the estimated duration
Understanding Test Duration
Sample Size Calculation: The calculator uses an industry-standard formula that accounts for both your baseline conversion rate and the minimum effect you want to detect.
Daily Traffic Split: The calculator assumes an equal 50/50 split of your daily traffic between the control and test variations.
Confidence Level: A higher confidence level (e.g., 99% vs. 95%) increases the required sample size. Industry standard is 95%.
Statistical Power: This calculator uses a fixed 80% power level, which is the standard for most A/B tests and balances the risk of false negatives.
Best Practices for A/B Testing
- •Run the full duration: Even if you see promising results early, run the test for the full recommended duration to ensure statistical validity.
- •Include full business cycles: Make sure your test duration includes full business cycles (e.g., weekdays and weekends) to account for traffic variations.
- •Test one change at a time: To clearly understand what impacts your conversion rate, test one element at a time.
- •Document everything: Keep detailed records of what you tested, why, and the results for future reference.
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Ready to run smarter A/B tests?
Humblytics makes it easy to launch A/B tests, track results in real-time, and get AI-powered insights—all without writing code.