Sample Size Calculator

Estimate the minimum sample size or duration required to support your experiment design. Try LaunchDarkly Experimentation for free to maximize the impact of every feature release.

Effect to sample size and durationSample size and duration to effect

Minimum detectable effect

Relative effect

Absolute effect

Sample size and duration

Exposure rate

units/day

Duration

days

Sample Size

units/day

Alternative Hypothesis info icon

Two-sided

Used to determine if the test variation is different from the control

Upper-tailed

Used to determine if the test variation is better than the control

Lower-tailed

Used to determine if the test variation is worse than the control

Control mean

Control standard deviation

Significance level (α)

Treatment allocation

Standard deviation ratio

Power (1-β)

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