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THE FEUTEX TOOLKIT

Welch Two-Sample Test Statistic

Calculate Welch’s two-sample statistic and approximate degrees of freedom from group summaries.

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01 Your input
02 Your result
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FormulaT = (m1-m2)/sqrt(s1**2/n1+s2**2/n2); Df = (s1**2/n1+s2**2/n2)**2/((s1**2/n1)**2/(n1-1)+(s2**2/n2)**2/(n2-1)); Difference = m1-m2
Sources and model references

How to use this tool

  1. Enter the labeled inputs using consistent units.
  2. Check the stated assumptions and calculate.
  3. Review each output and compare another input scenario.

Try this example

{
  "m1": 12,
  "m2": 10,
  "s1": 3,
  "s2": 4,
  "n1": 25,
  "n2": 25
}

Accuracy and scope

Independent samples with finite variances; outputs statistic and approximate degrees of freedom, not a p-value. Finite floating-point arithmetic; results can lose precision near singular or extreme inputs.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.