Standard Deviation Calculator
sigma, variance, mean, median for any dataset
📚 Learn more — how it works, FAQ & guide Click to expand
Learn more — how it works, FAQ & guide
Click to expand
Standard deviation calculator
Calculate σ, variance, mean, median, mode, range for any dataset.
How to use this tool
- 1
Paste numbers
Separate with commas, spaces, or new lines.
- 2
Pick dataset type
Population (entire set) or sample (n-1 denominator).
- 3
See full stats
Mean, median, mode, variance, σ, range, min, max.
Frequently Asked Questions
Population vs sample σ
Population divides by n. Sample divides by n-1 (Bessel correction) to account for estimation error.
What σ tells you
Standard deviation measures spread. 68% of values fall within ±1σ of the mean. 95% within ±2σ. 99.7% within ±3σ.
You might also like
🔒
100% Privacy. This tool runs entirely in your browser. Your data is never uploaded to any server.