Odds Ratio Calculator

Calculate the odds ratio, 95% CI, and p-values for case-control studies.

ExposedUnexposed
Cases
Controls
Total00

Limits: max 2 rows, 2 columns, values up to 999,999,999

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Fill out the form and click "Calculate" to see the calculation results.

Formula

The odds ratio (OR) is calculated using the values from a 2×2 contingency table:

OR=a×db×cOR = \frac{a \times d}{b \times c}

Where:

  • a = number of cases (disease) among the exposed,
  • b = number of controls (no disease) among the exposed,
  • c = number of cases among the unexposed,
  • d = number of controls among the unexposed.