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Both calculators run independently — change the inputs on either side to compare results.
Statistics
Standard Deviation Calculator
Compute the sample standard deviation directly from three summary statistics — sample size n, the sum of values Σx, and the sum of squared values Σx². This is the spread metric used in virtually every empirical study, quality-control chart, and risk model.
Fill in the required fields to see your result.
Statistics
Z-Score Calculator
Convert any raw value into a z-score — the number of standard deviations it sits above or below the mean of its distribution. Used everywhere from standardised test reporting and quality control to risk modelling and machine-learning feature scaling.
Fill in the required fields to see your result.
Key differences
| Standard Deviation Calculator | Z-Score Calculator | |
|---|---|---|
| Category | Statistics | Statistics |
| Inputs required | 3 | 3 |
| Result | Standard Deviation | Z-Score |
| What it does | Compute the sample standard deviation directly from three summary statistics — sample size n, the sum of values Σx, and the sum of squared values Σx². This is the spread metric used in virtually every empirical study, quality-control chart, and risk model. | Convert any raw value into a z-score — the number of standard deviations it sits above or below the mean of its distribution. Used everywhere from standardised test reporting and quality control to risk modelling and machine-learning feature scaling. |