Standard Deviation Calculator
Sample or population SD and varianceRuns locally · nothing uploaded
Standard deviation
5.237229
Variance
27.428571
Mean
18
- Count n8
- Sum144
- Sum of squares Σ(x − x̄)²192
- Standard error1.85164
- Coefficient of variation29.1%
- Minimum10
- Maximum23
- Range13
Steps
1. Mean x̄ = 144 ÷ 8 = 18
2. Sum of squared deviations Σ(x − x̄)² = 192
3. Variance = 192 ÷ 7 = 27.428571
4. Standard deviation = √27.428571 = 5.237229
Also works as:variance calculatorsample standard deviationpopulation standard deviation
How to use
- 1Choose sample or population.
- 2Paste numbers separated by commas, spaces or new lines.
- 3Read the SD, variance and the step-by-step working.
FAQ
Sample vs population standard deviation?
Use population (divide by n) when you have every member; use sample (divide by n − 1) when estimating from a sample. In Excel: STDEV.P vs STDEV.S.
What does standard deviation tell me?
How spread out values are around the mean. In a normal distribution about 68% fall within ±1 SD.