Education and School Calculations

Calculate confidence intervals for one mean, two independent means, one proportion, or the difference between two proportions.

Calculate p-values from z, t, chi-square and F statistics with one-sided or two-sided tails and significance interpretation.

Calculate sample size for surveys, means and two-group comparisons with confidence, power, finite-population correction and completion allowance.

Calculate chi-square goodness-of-fit and independence tests with p-value, critical value, expected counts, and effect size.

Calculate one-sample, independent, paired and Welch t-tests from raw data with t, degrees of freedom, p-value, effect size and confidence intervals.