The P-Value Calculator helps you determine statistical significance from test statistics. Compute p-values from z-scores (one-tailed or two-tailed), t-statistics with degrees of freedom, or chi-square statistics. The calculator provides step-by-step working and a visual shaded region showing the p-value area under the distribution curve.
Enter your test statistic, choose the distribution type and tail direction, and get instant results with significance interpretation at any alpha level.
Your calculations will appear here
Calculate probability of events, complements, unions, and intersections. Free online probability calculator for statistics.
Calculate standard deviation, variance, mean, and more for any dataset. Supports population and sample statistics. Free online tool.
Calculate z-scores, find values from z-scores, and determine probabilities. Free online z-score calculator with bell curve visualisation.
Calculate binomial probabilities, cumulative distributions, and expected values. Free online binomial distribution calculator with bar chart.
Calculate probabilities for normal distributions. Find areas under the bell curve, percentiles, and inverse values. Free online tool.
Calculate Pearson correlation coefficient, R-squared, and regression line. Free online correlation calculator with scatter plot.