Statistics calculators

Sample & population standard deviation with steps.

Population & sample variance with steps.

The core measures of central tendency, instantly.

Compute %CV from data or mean and standard deviation.

Quartiles, IQR, percentiles, and a box plot.

Measure distribution asymmetry.

Excess kurtosis (sample & population).

OLS line, slope, intercept, and R².

Pearson r for paired data, with a scatter plot.

Find p-values from a test statistic, with interpretation.

CI for a mean using the z- or t-distribution.

One- and two-tailed tests with a decision.

Compare two population means.

Required sample size for a survey or study.

Goodness-of-fit and independence tests.

Compare the means of three or more groups.

Convert a value to a z-score and percentile.

Probabilities and percentiles for any normal distribution.

Probability of two events (AND, OR, conditional).

nCr, nPr, and factorials.