Use this calculation to reproduce a defined quantitative method when the observations, units, sampling process, and assumptions match the method shown here.

First sample variance

Required number.

First sample size

Required integer.

Second sample variance

Required number.

Second sample size

Required integer.

The cited overview of Pooled variance supplies background for the terminology and domain context used by this tool.^[1]

Calculate pooled sample variance from two sample variances and sizes. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Pooled variance

Returned number.

• A numerical result does not by itself establish data quality, causation, representativeness, independence, distributional fit, or practical significance.
• First sample variance must be at least 0.
• First sample size must be at least 2.
• Second sample variance must be at least 0.
• Second sample size must be at least 2.
• Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.

Inspect the underlying data, visualize its distribution, report uncertainty and sample size, and compare the result with a robust or domain-specific method where appropriate.

• Pooled Standard Deviation Calculator

  Calculate pooled sample standard deviation from two sample variances and sizes.

• Two-Sample T-Test Calculator

  Calculate Welch's or pooled two-sample t-test statistic.

• F-Statistic Calculator

  Calculate an F statistic as the ratio of two variances.