The Coleman-Liau Index estimates the US grade level of your text using letters instead of syllables, which makes it easy to compute mechanically and reliable for machine analysis. It relies on two averages measured per hundred words: the average number of letters and the average number of sentences. The formula is 0.0588 times the average letters per hundred words minus 0.296 times the average sentences per hundred words minus 15.8. Because it skips syllable counting, it avoids the ambiguity that other formulas run into with unusual spellings. A result near 8 suits general readers, while higher numbers signal denser, more academic prose. This calculator recomputes as you type and does all the work locally in your browser, so your writing is analyzed privately and no text is ever transmitted to any server.
It computes a US grade level from the average number of letters and sentences per hundred words, so it counts characters rather than syllables.
Coleman-Liau uses letters instead of syllables because character counts are easier to compute reliably, making it good for automated scoring.
It is useful when you want a grade level that avoids syllable counting, which can be error prone for unusual words.
The Coleman-Liau Index estimates the US grade level of your text using letters instead of syllables, which makes it easy to compute mechanically and reliable for machine analysis. It relies on two averages measured per hundred words: the average number of letters and the average number of sentences.
Yes. Coleman-Liau Index Calculator is completely free, with no sign-up and no usage limits.
Yes. Coleman-Liau Index Calculator runs in any modern web browser. There is nothing to download or install.
Yes. Coleman-Liau Index Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.