Standard Deviation Calculator
Enter a list of numbers to calculate standard deviation. Choose sample or population mode and see mean, variance, count, min, and max.
Standard Deviation Calculator tool
Separate values with commas, spaces, or new lines. Example: 10, 12 15 20
Result will appear here.
| Metric | Value |
|---|
Privacy: calculations run locally in your browser. No values are stored or transmitted.
Population SD: σ = √(Σ(x−μ)² / N)
Sample SD: s = √(Σ(x−x̄)² / (N−1))
Examples
- Population example: 2, 4, 4, 4, 5, 5, 7, 9 → SD = 2
- Switch to sample mode when your values are a subset of a larger population
FAQ
- What is standard deviation?
Standard deviation measures how spread out values are around the mean. A larger value means more variation.
- What is the difference between sample and population standard deviation?
Population standard deviation divides by N. Sample standard deviation divides by N−1 to estimate spread from sample data.
- What separators can I use?
You can separate numbers with commas, spaces, tabs, or new lines.
- Are my numbers stored?
No. All calculations run locally in your browser and are not sent to a server.