σMATH
Standard Deviation Calculator
Calculate population or sample standard deviation from a list of numbers.
Enter your values
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Formula
Population SD = √(Σ(x − mean)^2 ÷ N). Sample SD uses N − 1 in the denominator.
Population SD = √(Σ(x − mean)^2 ÷ N). Sample SD uses N − 1 in the denominator.
How it works
1
Enter the data values.
2
Choose population or sample.
3
Review the mean, variance and standard deviation.
Important notes
Use sample mode when your values represent a sample and population mode when they are the complete population.