Average & Standard Deviation Calculator
Count
8
Sum
40
Mean (average)
5
Median
4.5
Mode
4
Range
7
Min
2
Max
9
Population variance
4
Population std. dev.
2
Sample variance
4.5714
Sample std. dev.
2.1381
About Average & Standard Deviation Calculator
Paste a list of numbers and get every common statistic at once — mean, median, mode, range, variance, and standard deviation, both population and sample.
Basic descriptive statistics come up constantly — in a spreadsheet, a lab report, a set of test scores — and computing them by hand for anything more than a handful of numbers is tedious and error-prone. Paste the whole list and every statistic updates together.
Population and sample standard deviation are genuinely different numbers, not two names for the same thing — population divides by the count, sample divides by the count minus one, which corrects for the fact that a sample tends to underestimate the true spread of the whole population it was drawn from. Both are shown, so it's clear which applies: population when the list is the entire group you care about, sample when it's a subset standing in for a larger one.
Mode shows every value tied for most frequent, and shows nothing when every value in the list is unique — a dataset with no repeats genuinely has no mode, rather than defaulting to the smallest or first value.
What you can use it for
- Find the mean and standard deviation of a set of test scores or measurements.
- Check the median of a dataset where outliers would skew the average.
- Compare a sample's standard deviation to a whole population's.
- Find the range and mode of a list of values.
- Get every basic statistic for a small dataset without opening a spreadsheet.
How it works, step by step
- 1
Paste your numbers
Separate them with commas, spaces, or new lines.
- 2
Read the statistics
Count, sum, mean, median, mode, range, and both variance/standard deviation figures update together.
Frequently asked questions
What's the difference between population and sample standard deviation?
Population divides the sum of squared differences by the count; sample divides by the count minus one. Use population when your list is the entire group; use sample when it's a smaller group representing a larger one.
Why does my dataset show no mode?
The mode is the most frequently occurring value. When every number in the list appears exactly once, there is no meaningful mode to show.
How is the median calculated for an even-length list?
As the average of the two middle values once the list is sorted — the usual definition.
Is my data uploaded anywhere?
No. Every statistic is computed entirely in your browser.