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Statistics / FREE CALCULATOR
Express distance from a mean in standard-deviation units.
Your answer starts here.
Enter your values and select Calculate to see the result and any available breakdown.
How to use this calculator
- Enter observed value. Use the unit shown beside the field.
- Enter reference mean. Use the unit shown beside the field.
- Enter reference standard deviation. Use the unit shown beside the field.
- Select Calculate and review the result. Select Reset to restore the example inputs.
How the calculation works
(Observed value-Reference mean)/Reference standard deviation
Worked example
Observed value = 120; Reference mean = 100; Reference standard deviation = 10. Result: 2 standard deviations.
Understand your result
Express distance from a mean in standard-deviation units. The result is expressed in standard deviations.
Assumptions and limitations
Does not establish normality or a probability by itself. Results are rounded for display.
Questions about this tool
What does this tool calculate?
Express distance from a mean in standard-deviation units.
What should I check before using the answer?
Does not establish normality or a probability by itself.
Related guides
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