Math Calculators
P-value Calculator
Find the p-value from a test statistic.
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About the P-value Calculator
Enter a z test statistic and choose a one- or two-tailed test to get the p-value from the standard normal distribution, plus a plain-English significance verdict at α = 0.05. It's the fast way to finish a hypothesis test once you have your z-score.
How to use the P-value Calculator
- 01Enter your a z-score and the test type.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
How do I get a p-value from a z-score?
Enter the z-score and pick two-tailed, right-tailed, or left-tailed. The calculator returns the corresponding area under the standard normal curve.
What does the p-value mean?
It's the probability of a result at least as extreme as yours if the null hypothesis were true. Below 0.05 is commonly called statistically significant.