๐Z-Score Calculator
Convert between a z-score and a percentile with a shaded bell curve.
Free Z-Score Calculator
Trying to find how a value compares to the rest of a normal distribution? Our free z-score calculator converts between raw scores, z-scores, and percentiles instantly โ with a shaded bell curve so you can see exactly what the number means.
Enter a value along with the mean and standard deviation to get its z-score, or enter a z-score directly to find its percentile and the area under the curve to the left, right, or between two points. Every result comes with the formula shown step by step, so you understand the calculation, not just the answer.
Built for statistics students, researchers, and anyone checking a z-table by hand, this tool replaces manual lookup tables with instant, accurate results. See the About page or the FAQ for more.