Standard deviation calculator
Paste your values to calculate standard deviation and a complete descriptive statistics summary.
How to use this page
- Paste at least two values.
- Use s for a sample or σ for a population.
- Check quartiles and range before interpreting spread.
What this page does not do: The measure is sensitive to outliers. The sample or population formula must match what the data represents.
Further reading
Standard deviation measures the typical distance of values from their mean. A sample uses n−1 in the denominator, while a complete population uses n.
The same input also produces the five-number summary, R7 quartiles, IQR, range and mode.
Frequently asked questions
When should I divide by n−1?
Use n−1 when the values are a sample used to estimate the variability of a larger population.
Is a small standard deviation always good?
No. Its meaning depends on the unit, scale and purpose of the analysis.
See also
ACF and PACF autocorrelation calculator
Calculate ACF and PACF across time-series lags. Review the chart, reference bounds and coefficient table.
Adjusted R-squared calculator
Convert R² to adjusted R² using the number of observations and predictors in a regression model.
Beta distribution calculator
Calculate beta density, CDF, upper tail and quantile together with its mean and variance.