Kruskal Wallis Test Calculator
Compare two or more independent groups using pooled average ranks, tie correction and an asymptotic chi-square tail.
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Result
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Calculation steps
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How to calculate
Pool observations, rank with average ties, partition group rank sums and correct H for repeated values.
H=[12Σ(Rg²/ng)/(N(N+1))−3(N+1)] / [1−Σ(t³−t)/(N³−N)]
Worked example
Groups A=[1,1,1], B=[2,2,2], C=[2,2] give tie-corrected H=7 and chi-square df=2 p≈0.03019738. These small groups also trigger a small-group limitation count.
Assumptions and input details
2–20 independent groups and 4–1000 total observations. Complete numeric data only. The p-value is asymptotic, with groups below five observations explicitly counted; it is not an exact permutation test. All-identical values leave H undefined. Location/median interpretation needs comparable distribution shapes. This omnibus calculation does not identify differing pairs or support repeated measures.
References: SciPy: Kruskal-Wallis tie correction and small-group caveats
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
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The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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