Statistics
Variance Calculator
Use this variance calculator to measure average squared spread from the mean.
Try an example
Result
Variance
—
- Mean
- —
- Standard deviation
- —
- Count
- —
Student quick launch
Grade planning, algebra checks, and formulas students reach for most.
Study path
Use this calculator with
Follow these when you want the formula behind the answer, a short lesson, or nearby tools in the same topic.
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 A smaller group taken from a population, used to estimate facts about the whole group. or Every member of the group you actually care about, not just the ones measured..
- Read variance and its square root, A number saying how far, on average, the data values sit from the mean..
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.
About this calculator
- Written by
- mathcheck editorial team
- Last reviewed
- May 15, 2026
Method
- Uses the values entered by the user and stable formulas documented on the page.
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Last updated: May 15, 2026