Percentage calculator
Calculate percentages online, including percent of a number, percentage increase, and percentage decrease.
Standard deviation calculator
Calculate sample or population standard deviation and variance with step-by-step deviations, z-scores, and standard error.
How to use Standard deviation calculator
Calculate the standard deviation and variance of a data set, with each step shown.
- Sample (divides by n − 1) when your data is a sample from a larger group
- Population (divides by n) when you have every value
The table lists each value's deviation from the mean, squared deviation, and z-score. You also get the standard error, coefficient of variation, and the range that holds about 68% of a normal distribution.
Standard deviation calculator FAQs
Is Standard deviation calculator free?
Standard deviation calculator is a free online tool on ReallyUseful.Tools. No account is required.
Does Standard deviation calculator run in my browser?
Standard deviation calculator is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.
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