Standard Deviation Calculator
Sample and population standard deviation and variance of a list of numbers.
Runs in your browser · No uploads
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- Nothing leaves your device
- No server-imposed size limits
- No sign-up, no watermark
- Free
How to calculate standard deviation
- Type or paste your numbers.
- Read the sample standard deviation, and the population one below it.
- Copy the results if you need them.
The formula
Find the mean, square each value's distance from it, add them up, divide by n − 1 (sample) or n (population), and take the square root. For 2, 4, 4, 4, 5, 5, 7, 9 the population standard deviation is exactly 2.
Frequently asked questions
Is anything sent anywhere?
No. The calculation happens in your browser, and your data never leaves your device.
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