Confidence Interval Calculator

Compute clean, publication ready confidence intervals for means and proportions. Paste raw data or summary stats. Auto choose z or t, Wilson or Agresti-Coull for proportions, Welch or pooled for two means. Try bootstrap from raw data and plan sample size for a target margin. Everything runs in your browser.

Local only Auto z or t Wilson & Agresti-Coull Bootstrap Sample size

Inputs

%

Keyboard: Enter compute, Ctrl+C copy results.

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See Confidence Intervel Calculator uide on SnipText Blog Page here.

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