Standard Deviation Calculator
Calculate the population or sample standard deviation, variance, and mean of a dataset.
How it works
- 1Enter your numbers separated by commas or spaces.
- 2Choose population (÷ n) or sample (÷ n−1).
- 3Read the standard deviation, variance, and mean.
Use cases
- Measure how spread out test scores or measurements are.
- Compute sample standard deviation for a statistics class.
- Assess volatility or consistency in a dataset.
Frequently asked questions
What is the difference between population and sample?
Population standard deviation divides by n; sample divides by n−1 (Bessel’s correction) to estimate spread from a sample.
What is variance?
The average of the squared differences from the mean. Standard deviation is the square root of variance.
When should I use sample?
Use sample when your data is a subset drawn from a larger population you want to estimate.
Related tools
See all →Calculate the area and perimeter of a rectangle from its width and height, with a labeled diagram.
Calculate the area and circumference of a circle from its radius, with a labeled diagram.
Calculate the area (Heron’s formula) and perimeter of a triangle from its three sides.
Calculate the area and perimeter of a trapezoid from its two parallel sides, height, and legs.