Standard Deviation Calculator
Enter numbers to compute population σ, sample s, variance, mean, and sum. Results update instantly.
100% client-side · no upload
Population σ
Sample s
Mean (x̄)
Pop. Variance (σ²)
Sample Variance (s²)
Count (n)
How to use
- Enter your numbers separated by commas or spaces into the text box.
- Click Calculate. Population σ uses n in the denominator; sample s uses n−1 (Bessel's correction).
- Use population σ when your data is the entire population; use sample s when it is a sample of a larger group.
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常见问题
- Is this standard deviation calculator free?
- Yes, completely free with no signup and no usage limits.
- Does my data leave my device?
- No. All calculations happen in your browser. Your dataset is never sent to any server.
- Does it work on mobile?
- Yes. Works on iPhone Safari and Android Chrome without installing any app.