Statistics Calculator
Free statistics calculator — mean, median, mode, range, variance, and standard deviation (sample and population) from any list.
Everyday Uses
Homework and exams
Check every statistic your assignment asks for in one paste — with sample vs population handled correctly.
Grading and scores
Teachers can paste a class's test scores to see the average, spread, and outliers instantly.
Small business insight
Paste daily sales to find your typical day (median) and how volatile revenue really is (std dev).
Lab data analysis
Mean and standard deviation of repeated measurements — the backbone of every lab report.
Frequently Asked Questions
What is the difference between mean, median, and mode?
The mean is the arithmetic average (sum ÷ count). The median is the middle value when sorted — half the data lies above, half below. The mode is the most frequent value. For skewed data like incomes, the median describes "typical" better than the mean, which a few extreme values can drag upward.
Sample vs population standard deviation — which should I use?
Use sample standard deviation (dividing by n−1, Bessel's correction) when your data is a subset of a larger group you're trying to describe — the usual case for surveys and experiments. Use population standard deviation (dividing by n) only when you've measured every member of the group. For large n the difference becomes negligible.
What does standard deviation actually tell me?
How spread out the data is around the mean, in the same units as the data. For roughly bell-shaped data, about 68% of values fall within 1 standard deviation of the mean and 95% within 2. A small SD means consistent values; a large one means high variability.
What if my data has no mode or several modes?
If every value appears exactly once, there is no mode — this calculator reports "None". If two or more values tie for the highest frequency, the data is multimodal and all tied values are listed. Multimodality often hints that your data mixes two distinct groups.