Standard Deviation Calculator

Calculate population or sample standard deviation, variance, mean, standard error, confidence intervals, and a frequency table for any data set.

Standard Deviation Calculator

Enter numbers separated by commas, spaces, or line breaks.

Calculate the standard deviation, variance, and mean of any dataset instantly with our free standard deviation calculator, useful for statistics coursework, research, and data analysis.

How It Works

Standard deviation measures how spread out data points are from the mean. Formula: σ = √(Σ(x − mean)² ÷ N) for population standard deviation, or dividing by (N−1) for sample standard deviation.

How to Use This Calculator

  1. Enter your data values, separated by commas or line breaks
  2. Select population or sample standard deviation
  3. Click Calculate to see mean, variance, and standard deviation

Frequently Asked Questions

What's the difference between population and sample standard deviation?

Population standard deviation is used when your data represents an entire population; sample standard deviation (dividing by N−1) is used when your data is a sample meant to estimate a larger population's spread.

What does a high standard deviation mean?

A high standard deviation indicates data points are spread widely from the mean; a low standard deviation means data points cluster closely around the mean.

How is standard deviation different from variance?

Variance is the average of squared deviations from the mean; standard deviation is the square root of variance, expressed in the same units as the original data.

Can this calculator handle large datasets?

Yes, you can enter as many data points as needed; just ensure they're properly separated for accurate parsing.