Chi-Square (χ²) Test Calculator

AP Biology — Statistical Analysis of Genetic Crosses

Stage 1–2: Enter Observed Counts

Category Observed (O) Expected Ratio Expected Count (E)
Total

Stages 3–5: Step-by-Step Calculation

Category O E (O − E) (O − E)² (O − E)² / E
χ²  =  Σ(O − E)² / E  =

Stage 5: Decision at p = 0.05

Degrees of Freedom (df) Critical Value (p = 0.05)