About the Standard Deviation Calculator
Standard Deviation Calculator does the math for you. Enter your values in the format shown and the result appears immediately — no spreadsheets, no formulas to remember, and nothing is uploaded to a server.
How Standard Deviation Calculator works
Population std dev = √(Σ(x−mean)² ÷ N).
Worked example: For 2,4,4,4,5,5,7,9: mean = 5, variance = 4, std dev = 2
How to use
- Enter your values as shown in the input box.
- The result is calculated instantly.
- Click Copy to use it.
Common uses
- Quick everyday math.
- Double-checking figures fast.
- Schoolwork and homework.
- Finance, health and planning.
Frequently asked questions
Is my data uploaded?
No — the calculation runs entirely in your browser, so your data stays private.
Is it free?
Yes — completely free with no sign-up.