Statistics Calculators

Statistics answers are only worth marks when the method is clear, and several of the methods come in more than one version. The main calculators here show the working line by line and say which convention they follow, so your answer matches the one your course expects.

The standard deviation calculator and the variance calculator build the table of differences from the mean and let you choose between a sample (divide by n − 1) and a whole population (divide by n). The quartile calculator finds Q1, the median, Q3 and the interquartile range. Textbooks and spreadsheets do not agree on how to find quartiles, so it offers three methods and names each one. The percentile calculator works both ways: the value at a given percentile, or the percentile rank of a given value. The linear regression calculator fits the line of best fit, shows the sums behind the slope and intercept, and reports r and r².

For counting problems, the permutation and combination calculator gives nPr and nCr together, with or without repetition, and the factorial calculator handles n! on its own. There is also a tool that lists every combination of a set of items, a geometric mean calculator and a simple graph plotter for data points.