Percentage calculator
Calculate proportions, increases, decreases and changes between values.
MATH
Understand your data: mean, median and spread.
Arithmetic mean
Example result · Adjust the inputs to make it yours
| Index | Value |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 4 |
| 4 | 4 |
| 5 | 5 |
| 6 | 5 |
| 7 | 7 |
| 8 | 9 |
UNDERSTAND THE HOW
We calculate mean, median and population standard deviation. Use a decimal point and separate values with semicolons, spaces or newlines.
mean = Σx / n; σ = √(Σ(x − mean)² / n)Up to 10,000 finite values, between −10¹² and 10¹². Population deviation, not sample deviation.
2;4;4;4;5;5;7;9: mean 5 and deviation 2.
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Formula visible · Updated September 8, 2026