Standard Deviation Calculator
Calculate sample and population standard deviation and variance with steps.
Enter your values to see the result.
Continue your work
- Statistics Calculator — Get every summary statistic.
- Mean, Median & Mode Calculator — Find the averages.
Share this tool
Found it useful? Send it to a friend or teammate.
Rate this tool
0.0
0 ratings
- 5 stars 0
- 4 stars 0
- 3 stars 0
- 2 stars 0
- 1 star 0
Clear instructions
Find steps, examples and limitations below.
Use online
Open the tool in a supported web browser.
Free to use
No sign-up required. Tool-specific limits may apply.
How to use the Standard Deviation Calculator
Calculate sample and population standard deviation and variance with steps.
- 1 Paste your numbers.
- 2 Choose Sample or Whole population.
- 3 Read the result and follow the table of deviations and squares.
Example and practical tips
For 10, 12, 23, 23, 16, 23, 21, 16 the mean is 18 and the sample standard deviation is about 5.24.
Frequently asked questions
What does standard deviation measure?
How spread out the values are around the mean. A small value means the data are close together.
Why divide by n − 1 for a sample?
It corrects the tendency of a sample to underestimate the spread of the whole population (Bessel’s correction).
Report an issue
Something broken or not quite right? Tell us and we will look into it.