What is this calculator?
Calculate z-score and standard normal probabilities from raw score, mean, and standard deviation.
This mathematics calculators page is designed for quick checks, planning, and everyday decision support without forcing users through a heavy workflow.
How to use it?
Enter the required values in the calculator above, review any optional settings, and run the calculation. Check the result summary and reset the form when you want to try a different scenario.
For important decisions, compare the output with your own records and professional guidance where needed.
Formula or method
Z-score = (x - mean) / standard deviation.
Worked example
Example: if x = 85, mean = 70, and standard deviation = 10, the z-score is 1.5.