Variance Calculator

The Variance Calculator lets you compute the variance of a data set instantly. Whether you’re working with population or sample data, this tool gives you a quick answer, along with the option to show detailed steps and control how results are rounded.

Perfect for stats homework, data analysis, or quick checks, it updates live as you type.

Options
Sample Variance
Show Steps
Round Result

How to Use:

  1. Enter your numbers in the input box. You can separate them with commas or spaces.
  2. Use the Sample Variance toggle if you’re working with a sample instead of an entire population.
  3. Turn on Show Steps to see how the variance is calculated.
  4. Enable Round Result if you prefer cleaner output.
  5. Results appear instantly and flash on update.
  6. Export or copy the result using the buttons below, or clear everything to start over.

What Variance Calculator can do:

The Variance Calculator takes your numbers, calculates the mean, and then works out how spread out the values are from the mean. It squares the differences, sums them, and divides by the correct denominator (n or n−1) depending on whether you’re calculating population or sample variance.

If you enable step-by-step mode, you’ll see the mean, squared differences, and final variance. The tool handles all the formatting, rounding, and flash feedback no calculator needed.

Example:

Settings: Input: 10, 12, 23, 23, 16, 23, 21, 16 Sample Variance: ON Show Steps: ON Round Result: ON

Output:

Data: 10, 12, 23, 23, 16, 23, 21, 16
Mean: 18
Squared Differences: 64.00, 36.00, 25.00, 25.00, 4.00, 25.00, 9.00, 4.00
Sample Variance = 26.57

Common Use Cases:

This tool is ideal for students learning statistics, teachers demonstrating concepts, or anyone analyzing numerical data. Use it to test hypotheses, validate spreadsheets, or prep for exams.

Useful Tools & Suggestions:

If you’re digging into variance, you’ll probably want to check out the Z-Score Calculator too it’s great for figuring out how far a value strays from the mean. Or try Calculate the Mean. It gives you a baseline to actually make sense of the spread.

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