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Mean Length of Utterance (MLU) is a foundational measure in language assessment, giving…

August 27, 2026 · Maya G., CCC-SLP

Mean Length of Utterance (MLU) is a foundational measure in language assessment, giving us a window into a child's grammatical complexity. It's the average number of morphemes per utterance.

While crucial, calculating MLU by hand can be tricky, and consistency is key. A common mistake SLPs make is counting contractions like "don't" as one morpheme instead of two ("do" + "not"). These small details can impact your overall score.

To help ensure accuracy and save time, we have a free MLU calculator. It helps you check your hand counts quickly.

Free MLU calculator at slpdraft.com/free/mlu-calculator #SLP

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