Instructions

This calculator estimates the confidence limits for your data. These help you to know how uncertain you are about the average of your data. If your data are from replicates of a single run, then tolerance limits are also estimated. These help you to see what a customer would experience.

Standard Deviation can either be the Standard Deviation for several repeated runs or a pooled Standard Deviation or "Pure Error" from a designed experiment.

Degrees of Freedom is N-1 for repeated runs. If you are using Pure Error, look up the degrees of freedom your software reports.

The number of replicates for the average is always N.

Standard Deviation (s):

Degrees of Freedom for s:

Average (Mean):

Number of Replicates for the Average (N):


Confidence:
90% 95% 99%

Please enter the standard deviation, the associated degrees of freedom, the average, and the number of replicates for your average.