# Z-Score Calculator

> Calculate how many standard deviations a value sits from the mean, with percentile.

To calculate a z-score, enter a value, the population mean and the standard deviation. The z-score expresses how many standard deviations the value sits from the mean, and the percentile shows what proportion of a normal distribution falls below it.

**URL:** https://convertto.tech/t/z-score-calculator
**Category:** Calculators (https://convertto.tech/c/calculators)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Set the value (x).
2. Set the mean (μ).
3. Set the standard deviation (σ).
4. The result appears immediately — copy or download it.

## FAQ

### What does a z-score of 2 mean?

The value sits two standard deviations above the mean. In a normal distribution that puts it above roughly 97.7% of the data, which is why 2 is a common threshold for flagging an outlier.

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