Readability Checker

Many organisations set readability targets. Government plain-language guidelines ask for public information most people can understand on first reading; health and insurance regulators in several countries require patient leaflets and policy documents to meet reading-level limits; and content teams use scores to keep help articles, product pages and newsletters easy to follow. Checking a score before publishing takes seconds and catches the most common problem in professional writing: sentences that try to say too much at once.

The most widely used score runs from 0 to 100: higher means easier. It combines the average number of words per sentence with the average number of syllables per word. Most guidance aims for 60 to 70 for general audiences — roughly the level of a well-written newspaper — and higher for public information and instructions.

The other five formulas estimate the US school grade needed to understand the text on first reading. Flesch-Kincaid uses words per sentence and syllables per word. Gunning Fog counts words with three or more syllables. SMOG also counts long words and is popular for health information; it is most reliable for texts of 30 sentences or more. Coleman-Liau and the Automated Readability Index count letters instead of syllables. Because each formula weighs things differently, the checker also shows their average. A grade of 8 or lower suits most adult readers.

Shorten long sentences — split them at 'and', 'but' or 'which'. Prefer short, everyday words: use rather than utilise, help rather than facilitate, about rather than approximately. Use the active voice and address the reader directly. Break up long paragraphs and use lists for steps and options. Then check again: the list of long sentences shows exactly where to start. Remember that formulas measure surface features only; they cannot tell whether a text is well organised, accurate or interesting, so read it aloud as a final check.

Syllables are counted with English pronunciation rules, which are right for most words but occasionally miss by one, so scores are estimates. The formulas were designed for English prose; they give misleading results for other languages, poetry, lists, code and very short texts. Reading time assumes 238 words per minute for silent reading and speaking time 150 words per minute, typical averages for adults. Your text is analysed locally and never sent anywhere.