Free Sample Size Requirement for the Difference of Means Calculator - Given a population standard deviation 1 of σ_{1}, a population standard deviation 2 of σ_{2} a reliability (confidence) value or percentage, and a variation, this will calculate the sample size necessary to make that test valid.

This calculator has 4 inputs.

This calculator has 4 inputs.

n = Z-score_{α/2}^{2} x (σ_{1}^{2} + σ_{2}^{2})/SE^{2}

α = 1 - Confidence%

For more math formulas, check out our Formula Dossier

α = 1 - Confidence%

For more math formulas, check out our Formula Dossier

- confidence interval
- a range of values so defined that there is a specified probability that the value of a parameter lies within it.
- reliability
- the overall consistency of a measure
- sample size
- measures the number of individual samples measured or observations used in a survey or experiment.
- sample size requirement for the difference of means