Example
Enter 2, 4, 4, 4, 5, 5, 7, and 9 to compare population and sample results.
Math
Standard Deviation Calculator
Calculate sample or population standard deviation and variance.
● ToolEnter your information below
Population standard deviation2Population variance4Sample standard deviation2.138Sample variance4.571Mean5Count8
Use population when the entries are the entire group. Use sample when they represent part of a larger group.
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Plain-language reference
How this tool gets the answer
What it calculates
Calculate sample or population standard deviation and variance.
Method
Population variance divides squared differences by the number of values; sample variance divides by one fewer value.
Keep in mind
Rounding and unit conventions can affect the displayed result; retain enough precision for the decision you are making. This limitation is especially important when using the standard deviation calculator for a consequential or shared decision.
Page owner: Anchor Apps LLC · Calculation and content last verified August 9, 2026.