Central tendency and spread are the two pillars of descriptive statistics. This calculator computes mean (arithmetic average), median (middle value), mode (most frequent), range (max − min), and both population and sample standard deviations — all from a single list of numbers, with no spreadsheet or external software required.
The mean is sensitive to outliers — one extreme value pulls it significantly. The median is resistant to outliers, making it a better measure of central tendency for skewed distributions like income or house prices. The mode is the most frequently occurring value, most meaningful for categorical data or discrete distributions. Standard deviation tells you how spread out the values are around the mean.
Population SD (σ) divides by n; sample SD (s) divides by n−1. Use sample SD when your numbers are a subset of a larger dataset. Use population SD when you have every value in the group.
If two values both appear the same number of times (and more than any other value), the dataset is bimodal. This calculator lists all modes when there is a tie.
When the count is even, the median is the average of the two middle values after sorting. For the list [2, 4, 6, 8], the median is (4+6)/2 = 5.
Yes — data copied from a spreadsheet column pastes as newline-separated values, which this calculator accepts. You can also paste comma-separated or space-separated lists.
See also the Fraction Calculator, Percentage Calculator, and the full maths toolkit on Chunky Munster.