Standard Deviation Calculator

Sample and population SD, step-by-step solutions, margin of error, z-scores, and full descriptive statistics.

How It Works

  1. Enter your data set. Paste comma-separated numbers (need at least 2 values).
  2. Choose sample or population. Sample uses n-1 (Bessel's correction); population uses n.
  3. Step-by-step. Follow mean ? squared deviations ? variance ? standard deviation.
  4. Margin of error & z. See SEM with error bars and compute z-scores for any value.
  5. Full statistics. Mean, median, range, CV, SEM, and a frequency table.

Also try our Percentage Calculator or Statistics Calculators.

Enter values to see results.

Formula & Reference

σ = √(Σ(x−μ)²/n) ยท Sample uses n−1