# Calculate > p-Value

The p-Value tool computes p-Values for four different types of probability distribution (Normal, Student's t, Chi-square, and F) and three types of tests (left-tail, right-tail, two-tail), given a test statistic and degrees of freedom (if applicable).

The inputs to the tool are:

- Distribution: Normal, Student's t, Chi-square, or Fisher
- Type of Test: Left-tail, Right-tail, or Two-tail
- Test Statistic: Sample statistic based on the sample data
- Degrees of Freedom (DOF): Number of values that are free to vary after certain restrictions have been imposed on all values. Computation of p-Values for different distributions requires different number of DOF inputs:

- Normal: none
- Student's T and Chi-square: one DOF input
- F: DOF 1 and DOF 2

- Click Compute to start the p-Value computation. The result is shown on the log window.
- Click Clear to clear all inputs (set to default).