What is Z-Score Calculator?

Z-Score Calculator converts raw scores into standardized z-scores and vice versa. Enter an observed value along with the population mean and standard deviation to get the z-score, cumulative probability, and percentile rank — essential for statistics coursework and data analysis.

How to use

1. Enter the observed value (x), population mean (μ), and standard deviation (σ).
2. The calculator instantly computes the z-score, cumulative probability, and percentile rank.
3. Use the visual bell curve to see where your value falls in the distribution, or switch to reverse mode to find x from a z-score.

Result

A student scored 78 on an exam where the class mean was 70 with a standard deviation of 5. The z-score is 1.6, meaning they scored in the 94.5th percentile — better than 94.5% of the class.

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