Variance Calculator
Calculate population variance, sample variance, and standard deviation for 5 values.
The Variance Calculator measures how far a set of numbers are spread from their mean. Variance is the average of the squared differences from the mean.
Enter five data points and the calculator computes the mean, population variance (divides by N), sample variance (divides by N-1 using Bessel's correction), and the population standard deviation.
Variance is widely used in finance (portfolio risk), quality control (process variation), and research (data dispersion). Standard deviation is simply the square root of variance and is often preferred because it has the same units as the data.
Frequently Asked Questions
What is variance?
Variance measures the average squared deviation from the mean. It quantifies how spread out data points are.
Why divide by N-1 for sample variance?
Dividing by N-1 (Bessel's correction) gives an unbiased estimate of the population variance when working with a sample.
What is the relationship between variance and standard deviation?
Standard deviation is the square root of variance. Variance is in squared units, while standard deviation is in the original data units.