Z-score Calculator
Where does x sit inside a normal distribution? Z plus percentile both ways.
Z-score
1.25
- Percentile (below x)
- 89.44%
- Above
- 10.56%
How the Z-score Calculator works
The calculation follows the standard method used across the US — no shortcuts, no hidden assumptions. Here is exactly what happens behind the scenes:
Formula
z = (x − μ)/σ
Frequently Asked Questions
How does the Z-score Calculator work?
Enter your numbers above and results update instantly using standard formulas, computed entirely on your device.
Is the Z-score Calculator free to use?
Yes — completely free with no signup required, and it works on phones, tablets, and desktops.
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