Readability checker
Every hard sentence, adverb, passive, filler and repeated word, highlighted as you type. No length limit, and nothing leaves your browser.
What the highlights mean
- Very hard sentence
- All five readability formulas put this sentence at grade 14 or above, and its words average at least 1.55 syllables. Splitting it in two is almost always an improvement. A reader will manage it, but they will have to work.
- Hard sentence
- Grade 10 or above by the same consensus. Often fine in literary prose, and worth a second look in anything meant to be read quickly. A run of them together is the real signal.
- Passive voice
- An auxiliary followed by a past participle: "was written", "is being held". Passive is correct when the actor is unknown or beside the point. It costs you when it hides who did what.
- Adverb
- An "-ly" adverb of manner. The question to ask is whether a stronger verb would carry the meaning alone: "walked slowly" against "ambled". Names and adjectives that end in "-ly" are not flagged.
- Complex word
- A word with a plainer synonym — "utilize" for "use", "commence" for "begin". Hover it to see the alternatives. Only words whose replacement is a genuine synonym in ordinary prose are listed.
- Filler
- An intensifier or hedge that takes a word's place without doing its work: "very", "really", "somewhat", "arguably". Delete one and the sentence usually stands unchanged.
- Repetition
- The same word three or more times within fifty words. This is the echo a reader hears and a writer, having just chosen the word, stops noticing. Dialogue tags like "said" are never flagged: repeating them is settled craft advice.
How to read a Flesch Reading Ease score
The score runs from roughly 0 to 100 and answers one question: how much work does a reader have to do? It measures only two things — how long your sentences are, and how many syllables your words carry. It knows nothing about whether your writing is good.
| Score | Reads like | Typically |
|---|---|---|
| 90–100 | Very easy | Children's books, early readers |
| 80–90 | Easy | Middle-grade fiction, plain-language guides |
| 70–80 | Fairly easy | Commercial fiction, most journalism |
| 60–70 | Plain English | General non-fiction, the usual target |
| 50–60 | Fairly difficult | Literary fiction, serious essays |
| 30–50 | Difficult | Academic prose, legal writing |
| Below 30 | Very difficult | Technical papers, contracts |
A novel scoring 55 is not worse than one scoring 75. Cormac McCarthy and Elmore Leonard sit at opposite ends of this table and both are doing exactly what they intend. Use the score to find out whether your prose matches your intention, not to chase a number.
Questions
- What is a good readability score?
- For most books and general writing, aim for a Flesch Reading Ease score between 60 and 70, which is plain English at roughly an eighth-grade reading level. Commercial fiction usually sits between 70 and 85. Literary fiction runs lower, often 50 to 65, and that is not a fault — a lower score means longer sentences and longer words, which is a legitimate style. Academic and technical writing frequently falls below 30. The score describes your prose; it does not grade it.
- How is the Flesch Reading Ease score calculated?
- Flesch Reading Ease is 206.835 minus 1.015 times the average words per sentence, minus 84.6 times the average syllables per word. Higher is easier. The Flesch-Kincaid grade level uses the same two inputs on a different scale: 0.39 times words per sentence, plus 11.8 times syllables per word, minus 15.59, which returns roughly the US school grade needed to read the text.
- Is there a word limit?
- No. Paste an entire manuscript if you like. The analysis runs in your browser at roughly 0.06 microseconds per character, so a full-length novel is analysed in well under a second. Most online readability tools cap you at a few thousand words because they analyse on a server; this one does not need to.
- Does my text get uploaded anywhere?
- No. The analysis runs entirely in your browser. Your writing is never sent to a server, never stored, and never logged. You can disconnect from the internet after the page loads and the tool keeps working.
- Why is this sentence marked hard when it seems fine?
- A sentence is only highlighted when all five readability formulas — Flesch-Kincaid, Gunning Fog, ARI, Coleman-Liau and SMOG — agree it is above the threshold, and its average word carries at least 1.55 syllables. That second test matters: long sentences built from short Anglo-Saxon words are not hard to read, and flagging them is what makes most tools annoying. A highlight means length and density together.
- Should I remove every adverb and every passive?
- No, and any tool that implies otherwise is selling you a rule instead of a judgement. Passive voice is correct when the actor is unknown or irrelevant — 'the manuscript was rejected' is often exactly right. Adverbs earn their place when no single verb carries the meaning. Treat the highlights as a map of where your prose is working hardest, then decide each one yourself.
- What is the difference between this and Hemingway Editor?
- The findings are the same family: hard sentences, adverbs, passive voice, complex words. Three differences. This tool has no length limit. It adds a repetition pass, which flags a word used three or more times within fifty words — the echo a reader hears but a writer stops noticing. And it is the analyser that ships inside Nueel, so what you see here is what you would see over a whole book.
Writing a book?
This analyser is one panel inside Nueel, which turns the manuscript you have been writing in Word into a print-ready PDF and an EPUB the shops will accept. $139 once, in your browser.