P-Value Calculator

Inputs explained

• Z test statistic — The z-score from your hypothesis test.
• Test type — Two-tailed tests for any difference; one-tailed (right or left) tests for a difference in one direction.

How to use it

1. Fill in the fields above — each input has a hint describing exactly what to enter
2. Press Calculate to get your result instantly, right on this page
3. Copy the result, save the tool to favorites, or share and embed it anywhere

Understanding the result

Example: A z-statistic of 1.96 gives a two-tailed p-value of ≈ 0.05.

Frequently asked questions

What's the difference between choosing a one-tailed and two-tailed test? A two-tailed test checks for a difference in either direction and roughly doubles the p-value compared to a one-tailed test, which only checks for a difference in one specified direction; picking the wrong type can make a result look more or less significant than it should.

Does this calculator tell me if my result is statistically significant? It only computes the p-value from your z-statistic; you still need to compare that p-value to your own chosen significance threshold (commonly 0.05) to decide whether to call the result significant.

Is the P-Value Calculator free to use? Yes — it is completely free, with no sign-up, no download and no usage limits. You can use it as often as you need.

Is my data private? Yes. The calculation runs entirely in your browser — the values you enter are never sent to our servers, stored or shared with anyone.

What information do I need? Just the following: Z test statistic, Test type. Each field includes a hint explaining exactly what to enter.

Can I use it on my phone? Yes — the tool is fully responsive and works on any device, and the same calculator is available in the EasyWorkCalcs mobile app.

Privacy

Everything you enter into the P-Value Calculator is processed entirely in your browser. Nothing is uploaded, stored or shared — your data stays on your device.