Statistics Calculator
Standard deviation, variance and quartiles.
- Population std. deviation
- 12.315302
- Sample variance
- 182
- Population variance
- 151.666667
- Mean
- 18
- Minimum
- 4
- Q1
- 9.75
- Median
- 15.5
- Q3
- 21.25
- Maximum
- 42
- Count
- 6
How this calculator works
Standard deviation measures how spread out values are from the mean. Use the sample version when your data is a sample of a larger group.
Formula
s = √(Σ(x − x̄)² ÷ (n − 1))
Example
For 4, 8, 15, 16, 23, 42 the sample standard deviation is about 13.49.
When to use it
- Lab and survey data
- Quality control
- Finance volatility checks
Frequently asked questions
Should I use the sample or population standard deviation?
Use the population version when your data covers the whole group. Use the sample version when your data is a subset used to estimate a larger group.
What does a high standard deviation mean?
It means values are widely spread around the mean. A low value means they cluster closely together.
Learn more
How to calculate standard deviation, and what the number is telling you
Two groups can share the same average and look nothing alike. Standard deviation captures the difference. Here is how to calculate and read it.
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