Krippendorff's Alpha Calculator
Measure inter-coder reliability for content analysis. Paste one row per unit with the category code each coder assigned.
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Why Krippendorff’s alpha
Krippendorff’s alpha is the standard reliability measure for content analysis and coding studies. Unlike percent agreement it corrects for chance, and it handles any number of coders as well as missing values, so coders do not all have to rate every unit. This calculator uses the nominal difference function, which treats every pair of different codes as equally far apart.
How to read the value
Alpha ranges up to 1. The common threshold is 0.80: data at or above it are considered reliable. Values from 0.667 up to 0.80 are only tentatively acceptable, suitable for drawing cautious conclusions, and anything below 0.667 is usually treated as too unreliable to use.
Frequently asked questions
Can rows have different lengths?
Yes. If a coder did not rate a particular unit, simply leave that value out of the row. Krippendorff’s alpha is designed to handle missing ratings.
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