# Confidence Interval for Variance and Standard Deviation Calculator

 Enter N Enter Sample Variance s2 Enter Confidence Interval %

### How does the Confidence Interval for Variance and Standard Deviation Calculator work?

Calculates a (95% - 99%) estimation of confidence interval for the standard deviation or variance using the χ2 method with (n - 1) degrees of freedom.
This calculator has 3 inputs.

### What 4 formulas are used for the Confidence Interval for Variance and Standard Deviation Calculator?

1. Degrees of Freedom = n - 1
2. Square Root((n - 1)s22α/2) < σ < Square Root((n - 1)s2 / χ21 - α/2)
3. Square Root((n - 1)s22α/2) < σ2 < Square Root((n - 1)s2 / χ21 - α/2)

For more math formulas, check out our Formula Dossier

### What 5 concepts are covered in the Confidence Interval for Variance and Standard Deviation Calculator?

confidence interval
a range of values so defined that there is a specified probability that the value of a parameter lies within it.
confidence interval for variance and standard deviation
a range of values that is likely to contain a population standard deviation or variance with a certain level of confidence
degrees of freedom
number of values in the final calculation of a statistic that are free to vary
standard deviation
a measure of the amount of variation or dispersion of a set of values. The square root of variance
variance
How far a set of random numbers are spead out from the mean