MATH & NUMBERS
Standard Deviation Calculator
Compute mean, variance and standard deviation of a data set.
100% free
No sign-up
Private — runs in your browser
Instant results
KEY TAKEAWAYS
- Compute mean, variance and standard deviation of a data set.
- Free to use — no sign-up, no account and no usage limits.
- Runs entirely in your browser, so the numbers you enter stay private.
- Works on desktop and mobile with instant, accurate results.
Last updated: June 2026
About the Standard Deviation Calculator
Paste your numbers and choose sample or population to get the count, sum, mean, variance and standard deviation.
Frequently asked questions
Sample or population standard deviation?
Use sample (divide by n−1) when your data is a subset; use population (divide by n) when you have every value.
Free online tool from ConvertFleet. Calculations run entirely in your browser — nothing you type is sent anywhere. Results are estimates for general guidance only.