Standard Deviation & Variance Calculator

Calculate stable sample and population variance, standard deviation, mean, and range.

Numbers

Separate values with commas, spaces, semicolons, or new lines. Population measures use every value; sample measures use n − 1.

Count

Mean

Population variance

Population standard deviation

Sample variance

4.57142857

Sample standard deviation

2.13808994

Range

How to Use

The calculator uses Welford's stable one-pass algorithm. Sample variance is undefined for fewer than two values.

Population variance divides squared deviations by n; sample variance divides by n − 1.

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

Result: The calculator updates its results immediately from these inputs.

What does the Standard Deviation & Variance Calculator estimate?

Use population results for the full group and sample results when values are a sample of a larger population.

Find mean, median, mode, range, sorted values, and a frequency table for a dataset.

Calculate percentages, increases, decreases, discounts, and percentage differences instantly.