Math

Standard Deviation Calculator

Measure spread using sample or population variance and standard deviation for a numeric list.

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How to use Standard Deviation Calculator

Variance sums squared deviations from the arithmetic mean, divided by N for a population or N−1 for a sample. Standard deviation is its square root.

Up to 1,000 numbers. A sample requires at least two values. Inputs separated by commas or whitespace must not contain thousands separators.
Decimal inputs have at most 120 characters and magnitude from 1e-100 to 1e15, or zero. Floating-point results are rounded to 12 significant digits; extreme derived results may underflow or be rejected. Exact integer results are identified separately.

What calculation does Standard Deviation Calculator perform?

Variance sums squared deviations from the arithmetic mean, divided by N for a population or N−1 for a sample. Standard deviation is its square root.

Which convention should I choose?

Use Population when the list is the entire population of interest, or Sample when estimating population variability from a sample.

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