Z-Score Calculator
z = (x − μ) / σ — with percentile and tail probability.
See how it works
Watch a quick simulation of this tool in action — no file needed.
How to use Z-Score Calculator
Follow these steps — everything happens instantly in your browser.
- 1
Step 1. Enter the value x you want to test.
- 2
Step 2. Enter the mean μ and the standard deviation σ (must be positive).
- 3
Step 3. See the z-score, percentile and tail probabilities update instantly.
Why use this tool
Frequently asked questions
Everything you might want to know about z-score calculator.
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