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Calcimator

Fisher's Exact Test Calculator

Perform Fisher's exact test on a 2x2 contingency table to determine if there is a significant association between two categorical variables.

Inputs

Results

P-Value (two-tailed)

0.07

Odds Ratio

9.33

P-Value (one-tailed)1
Exact Probability of This Table0.03
Relative Risk2.67
Significant at α=0.05 (1=Yes)0
Col29
How to Use This Calculator
  1. Enter Cell A (Row 1, Col 1), Cell B (Row 1, Col 2), and Cell C (Row 2, Col 1).
  2. Set Cell D (Row 2, Col 2).
  3. Review P-Value (two-tailed) and Odds Ratio.
  4. Use P-Value (one-tailed) and Exact Probability of This Table to inform your decision.
  5. Use the chart to visualize the results and explore different scenarios by adjusting inputs.

How the result changes with Cell A (Row 1, Col 1)

Cell A (Row 1, Col 1)P-Value (two-tailed)Odds Ratio
1,00001,166.67
3,50004,083.33
6,50007,583.33
9,00009,999

What each input means

Cell A (Row 1, Col 1)
Count for Group 1, Outcome 1 (e.g., treatment group with positive outcome).
Cell B (Row 1, Col 2)
Count for Group 1, Outcome 2 (e.g., treatment group with negative outcome).
Cell C (Row 2, Col 1)
Count for Group 2, Outcome 1 (e.g., control group with positive outcome).
Cell D (Row 2, Col 2)
Count for Group 2, Outcome 2 (e.g., control group with negative outcome).

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Cell A (Row 1, Col 1) = 8, Cell B (Row 1, Col 2) = 2, Cell C (Row 2, Col 1) = 3, Cell D (Row 2, Col 2) = 7 = 4 input(s) provided
  2. Calculate P-Value
    P-Value
    0.06978 = 0.06978
  3. Calculate Odds Ratio
    Odds Ratio = Math
    9.3333 = 9.3333
  4. Calculate P-Value
    P-Value
    0.99726 = 0.99726
  5. Calculate Exact Probability of This Table
    Exact Probability of This Table
    0.03215 = 0.03215

Engine last updated . Checked against 2 independently-derived tests — how we verify calculators.

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