Math & Science
Standard Deviation Calculator
Calculate standard deviation and variance
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Frequently asked questions
What does the Standard Deviation Calculator do?
It helps you calculate standard deviation and variance.
What inputs do I need?
Enter Values.
Are decimals supported?
Yes, you can use decimal values where appropriate.
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About this tool
Inputs
- Values
Results
- Standard deviation
- Mean
- Count
Whether you are planning ahead or double-checking existing numbers, the Standard Deviation Calculator delivers instant answers from the figures you provide. Understanding the underlying principle helps you judge whether a result is reasonable. The required inputs are values. Once provided, the result — standard deviation, mean and count — appears instantly.
Having a dedicated tool to calculate standard deviation and variance saves time you would otherwise spend searching for formulas or setting up a spreadsheet. Every calculator on this page uses a well-defined formula — the same one you would find in a textbook, applied instantly. Double-check units before and after the calculation — a mismatched unit is the most common source of wrong answers. Compare multiple scenarios by saving or noting each result before changing inputs.