Statistics
Variance Calculator
Use this variance calculator to measure average squared spread from the mean.
Variance
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- Mean
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- Standard deviation
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- Count
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Student quick launch
Grade planning, algebra checks, and formulas students reach for most.
Study path
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What the variance calculator solves
Use this variance calculator to measure average squared spread from the mean.
Formula
How to use it
- Enter numbers separated by commas or spaces.
- Choose sample or population.
- Read variance and its square root, standard deviation.
How to read the answer
Variance is in squared units, so it is often paired with standard deviation for interpretation.
Common mistakes and edge cases
- Use sample variance for a sample from a larger population.
- Variance is sensitive to outliers.
- Do not compare variance across different units without context.
Worked examples
Sample variance
Variance
6.5
Population variance
Variance
4
Frequently asked questions
Is variance the same as standard deviation?+
No. Standard deviation is the square root of variance.
Why is sample variance divided by n - 1?+
The n - 1 denominator corrects bias when estimating population variance from a sample.
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Last updated: May 15, 2026