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. Useful for statistics coursework and data analysis.

How to use

1. Enter the observed value (x), population mean (μ), and standard deviation (σ).
2. It shows 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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