Readability Checker

Combines average sentence length with syllables per word. Higher values usually indicate easier reading. Scores commonly sit between 0 and 100, but the raw formula can extend beyond that range. It is distinct from the Flesch–Kincaid grade formula.

Uses sentence length and syllables to estimate a US school grade. A grade estimate describes language complexity; it does not certify that a passage is suitable for every reader at that grade.

Estimates reading grade from sentence length and the proportion of words with three or more syllables. GramProof uses an automated approximation without excluding proper names or familiar technical terms.

Uses polysyllabic words and sentence count to estimate reading grade. GramProof requires at least 30 sentences before showing this metric to avoid presenting a short sample as a standard SMOG assessment.

Estimates reading grade from the number of one-syllable words in a 150-word sample. Unlike many other formulas, it does not use sentence length. GramProof uses the first 150 words.

Estimates reading grade using letters and sentences per 100 words rather than syllables. This offers a different perspective when pronunciation-based estimates vary.

Uses average word length and sentence length to estimate reading grade. This English-text implementation counts letters in recognized words and excludes standalone numbers and punctuation.

Compares words against a revised familiar-word list and also considers sentence length. GramProof converts the formula’s index into a US grade band; the underlying index is not itself a grade.

The revised Spache formula combines sentence length and unfamiliar vocabulary. GramProof counts distinct words absent from the revised Spache list. This formula is intended for early elementary material, rather than advanced academic writing.

Weights words by syllable count in the first 100 words, then considers the sentences represented in that sample. It provides another estimated grade level for comparing drafts.