How to Use the Chi-Square Distribution with CHISQ.DIST.RT in Excel

Use CHISQ.DIST.RT to test whether observed counts match what you expected — like defects spread across production lines.

You will learn to

• Turn a chi-square statistic into a p-value
• Calculate the statistic from observed and expected counts
• Test against expectations weighted by volume

How it works

A chi-square goodness-of-fit test checks whether counts are spread the way you expected: defects across machines, complaints across weekdays, votes across options. The statistic adds up (observed − expected)² ÷ expected for every category; CHISQ.DIST.RT turns it into a p-value using degrees of freedom = categories − 1.

A small p-value (say under 5%) means the counts are unlikely under your expectation. The expectation matters: equal shares and shares weighted by production volume can lead to opposite conclusions.

=CHISQ.DIST.RT(7.96,3)