Skewness and Kurtosis Calculator
Paste your data to see whether it is skewed and how heavy its tails are.
Your numbers
Your results
Skewness and Kurtosis Calculator by TheCalcTools
How the Skewness and Kurtosis Calculator works
Skewness measures asymmetry. Positive skew means a long tail of high values (the mean is usually above the median); negative skew means a long tail of low values.
Excess kurtosis compares tail weight with a normal distribution, which has 0. Positive values mean heavier tails and more extreme values than a normal distribution.
This calculator uses the sample-adjusted formulas used by Excel’s SKEW and KURT functions. Labels use the common thresholds of 0.5 and 1.
The formula
Worked example
Using the default values shown in the calculator:
| Your data (at least 4 values) | 2, 3, 3, 4, 4, 4, 5, 5, 6, 9, 12 |
|---|
- The mean, 5.18, is above the median, 4, a first sign of right skew.
- Skewness = 1.5374 and excess kurtosis = 2.1525: Strongly right-skewed (long tail to the high side).
Result:
| Skewness | 1.5374 |
|---|---|
| Excess kurtosis | 2.1525 |
| Shape | Strongly right-skewed (long tail to the high side) |
| Mean | 5.1818 |
| Median | 4.0000 |
Frequently asked questions
What skewness is acceptable for a t-test or regression?
Many texts treat |skewness| below about 1 as acceptable for methods that assume normality, especially with larger samples. Always look at a histogram too.
Why do different programs give different values?
Some report the population formulas (g₁, g₂) and some the sample-adjusted ones (G₁, G₂). This calculator matches Excel and most statistics packages’ adjusted versions.
Sources and further reading
Related calculators
More in Statistics & Probability · All calculators
This calculator gives estimates for information only. Check important results independently before you rely on them. See our disclaimer.