Readability checker: reading grade, Flesch score and what to fix

Paste your text and see how hard it is to read, by six standard formulas — then see exactly which sentences are making it hard. Nothing is uploaded.

A score on its own doesn't tell you what to change. This checker marks up your text the way an editor would: long sentences shaded, passive constructions picked out, adverbs and qualifiers noted, and wordy phrases paired with a plainer alternative. Fix a few and watch the grade fall as you type.

The six scores

What each formula measures

Formula	Built from	Reads as
Flesch reading ease	Words per sentence, syllables per word	0–100, higher is easier; 60–70 is plain English
Flesch–Kincaid grade	The same, rescaled	US school grade
Gunning fog	Words per sentence, share of long words	Years of schooling
SMOG	Words of three or more syllables	Grade; designed for 30+ sentences
Coleman–Liau	Letters per word, sentences per word	Grade, with no syllable counting
Automated readability	Characters per word, words per sentence	Grade

The big number is the median of the five grade-level formulas, which is steadier than any single one. The scores were checked against textstat, an independent implementation, on passages from children's prose to legal drafting.

What gets highlighted

• Long and very long sentences — 25 and 35 words or more. Most can be split in two.
• Passive voice — “was approved by the board” rather than “the board approved”.
• Adverbs — often a sign that a stronger verb is available.
• Qualifiers — very, really, quite, just, sort of: words that usually weaken a sentence.
• Plainer words — “utilise” for “use”, “in order to” for “to”, with the alternative shown.
• Repeated words — “the the”, the typo every proofreader misses.

Click any highlight and the same words are selected in your text, ready to rewrite. Headings, tables and code are shown but kept out of the scores, because they are not sentences.

Check a Word document without uploading it

Online readability checkers send your text to a server to score it. That's a problem for a draft contract, an unannounced product or a patient letter. Here the Word file is opened and read inside your browser, using the same code as Recto's document converter, and the text never leaves your computer.

Questions

What is a good Flesch reading ease score?

For writing aimed at the general public, 60 to 70 is the usual target — Flesch called that plain English. Scores of 80 and above are easy, like popular fiction; under 30 is the territory of academic papers and legal contracts.

What reading grade should I aim for?

Grade 8 suits most writing for the public: it is roughly what an average adult reads comfortably, and easier text loses no one. Government plain-language guides commonly ask for grade 8 or lower. Technical writing for specialists can sit at 10 to 12.

Why do the formulas give different grades?

Each measures something slightly different. Flesch–Kincaid and SMOG count syllables, Coleman–Liau and the automated index count letters, and Gunning fog counts long words. The headline grade is the middle of the five, which is steadier than any one of them.

Does it upload my text?

No. Every count and every check runs in the page, in your browser. That makes it safe for unpublished drafts, client work, and anything under embargo.

Can I check a Word document?

Yes. Drop a .docx file onto the text box, or choose it with the file button. The text is pulled out in your browser and checked like anything else. EPUB, HTML and Markdown files work too.

How does it count syllables?

With spelling rules and a list of common exceptions, since no dictionary is shipped with the page. On the eight thousand most frequent words in a sample of ordinary English it agrees with the CMU Pronouncing Dictionary 99% of the time, weighted by how often each word appears.

Is passive voice always wrong?

No. It is right when the doer is unknown or beside the point — “the bridge was built in 1932”. It is flagged because it is often used to hide who is responsible or simply makes a sentence longer. Treat every highlight as a question, not a correction.

Does it work for languages other than English?

Not yet. The formulas, syllable rules and word lists are all built for English, and the scores would be misleading for other languages.

The other tools