Z-Score Calculator
Find how many standard deviations a value is from the mean, with percentile. The result updates as you type, with the working underneath so you can check it.
Your details
Result
Z-score
1.5000
- Percentile (area below)
- 93.32%
- Area above
- 6.68%
- Two-tailed p-value
- 0.1336
Good to know: z = (x − μ) ÷ σ
About this tool
Formula
z = (x − μ) ÷ σ
Questions people ask
What is a good z-score?
It depends on context. A z-score of 0 is average, ±2 is unusual (about 5% of values), and ±3 is rare.
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How we calculate this
We use the standard published formula or definition for this calculation, and we show the working so you can check it.
Spotted a mistake? Tell us and we'll check it. How we check our calculators