How to use this z-score calculator
Enter the values requested above and select Calculate. Change any input to compare another scenario. The calculation runs locally in your browser and does not require an account.
Formula and method
Example
A score of 85 in a distribution with mean 70 and standard deviation 10 has z = 1.5.
Tips for a useful result
Positive z-scores are above the mean; negative z-scores are below it.
What this calculator is useful for
Calculate a z-score from a value, mean and standard deviation. The result is intended for quick estimates, checking arithmetic and comparing scenarios. When a result affects a contract, tax filing, medical decision, building-code requirement or other high-stakes situation, verify the result with the appropriate professional or authoritative source.
Frequently asked questions
What does the Z-Score Calculator calculate?
Calculate a z-score from a value, mean and standard deviation.
How does the Z-Score Calculator work?
z = (x − mean) ÷ standard deviation.
Is the Z-Score Calculator free to use?
Yes. ERICH Calculators is free to use and does not require an account.