Free CRO Tools
Professional conversion optimization tools. No sign-up required.
A/B Test Calculator
Sample size + duration in one. Plan how many visitors you need and how long the test runs.
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Sample Size Calculator
Find exact visitors per variant for your MDE + significance + power. Two-proportion z-test.
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Significance Calculator
Input visitors + conversions. Get p-value, z-score, confidence, and winner determination.
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Revenue Impact Calculator
Translate any CR lift into annualized $ revenue lift. Plan-vs-actual ROI in seconds.
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Coming soon
CRO Score Checker
Scan your website for 50+ conversion issues in 60 seconds.
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AI Test Ideas
Get AI-powered A/B test suggestions for your page.
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