P-value Calculator
Find the p-value from a z-score.
Result
Results are estimates for general information only and are not professional advice.
P-values
A p-value is the probability of observing a result at least as extreme as your z-score if the null hypothesis is true. This calculator converts a z-score into a one- or two-tailed p-value using the standard normal distribution.
Frequently Asked Questions
What is the P-value Calculator?
Find the p-value from a z-score. It runs instantly in your browser and is completely free to use.
What do I need to enter to use the P-value Calculator?
The P-value Calculator asks for the following values (2): Z-score, Test type. Fill them in and the result appears immediately — the calculation runs on your own device, so nothing you type is sent to a server.
How accurate is the P-value Calculator?
The P-value Calculator uses standard, widely-accepted formulas, so its figures are reliable estimates for everyday planning. They are not a substitute for advice from a qualified professional.
Is the P-value Calculator free, and do I need an account?
Yes. The P-value Calculator — and every other calculator on Calculatis — is completely free, with no registration, no download and no limit on how often you use it.