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.
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.
How it works
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.