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Standard Deviation Calculator

Welford’s algorithm accumulates squared deviations.

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How standard deviation calculator works

Welford’s algorithm accumulates squared deviations. Population divides by n; sample divides by n−1. Values are normalized by the largest magnitude first to avoid intermediate overflow.

Try an example

2,4,4,4,5,5,7,9 has population standard deviation 2.

Good to know

Uses double-precision arithmetic; displayed values are rounded to 13 significant digits.

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