About this calculator
What the F-distribution is for
The F-distribution compares two variances. Its main use in intro statistics is one-way ANOVA, where F = (variation between groups) ÷ (variation within groups). It has two degrees of freedom: numerator df = k − 1 and denominator df = N − k for k groups and N total observations.
Like chi-square, F is never negative and is skewed right, and ANOVA tests are right-tailed.