Cold email A/B significance calculator
Compare two reply or meeting rates with confidence intervals and a two-sided z-test.
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Your result
Add your inputs, or try the example, to see your result here.
A low p-value does not prove causation or practical value.
How to use this tool
- Compute observed rates and Wilson 95% confidence intervals.
- Use a pooled two-proportion z-test for the difference.
What the result tells you
- A low p-value does not prove causation or practical value.
- Independent random assignment and a fixed analysis plan matter; opens are noisy.