How to check the readability of your writing
Readability is just how much work a reader has to do to understand you. Two things drive almost all of it: sentence length and word length. Long sentences make the reader hold more in their head; long, rare words slow them down. Every readability formula is a different way of weighing those two signals.
- Paste your text into the box above. The score updates live as you type — no button, no upload, nothing sent to a server.
- Read the highlights. Amber is possible passive voice, purple is filler, blue is adverbs, green marks very long words, and orange shading marks sentences that have grown too long. Toggle any category off with the chips.
- Use the actionable tips. Below the scores, ClearPen shows you the specific rewrites that will move your grade most — "split this sentence," "cut these filler words," "rewrite passive as active." Not just a number: a ranked, data-driven fix list.
Why ClearPen instead of Grammarly or Hemingway? Your text stays private — it never leaves your device. And the fix suggestions are tied directly to your text's data: passive count, exact sentence lengths, filler rate. You get a specific rewrite agenda, not generic style advice.
What the scores mean
Flesch Reading Ease runs from 0 to 100 — higher is easier. Around 60–70 is plain English that most adults read comfortably; below 30 reads like dense academic prose. Grade level (Flesch-Kincaid and the others) converts the same signals into a U.S. school grade, so "grade 8" means a typical 13–14-year-old could follow it. This tool shows a consensus grade — the average of several formulas — so you are not at the mercy of any single one.
Why passive voice and filler get flagged
Neither is wrong. Passive voice ("the report was written") hides who did something; in most writing, naming the actor ("the team wrote the report") is shorter and clearer. Filler words ("very", "really", "just", "in order to") feel natural in speech but rarely earn their place on the page. The checker points them out; you decide which to keep.
Want the science behind the numbers? See the Flesch-Kincaid calculator for the exact formulas, or the reading level checker for how grade levels map to audiences.
Frequently asked questions
What is a good readability score?
For a general audience, aim for a Flesch Reading Ease of about 60 to 70 — roughly an 8th- to 9th-grade reading level. Marketing and web copy often target 60 or higher; technical or academic writing naturally scores lower. The right target depends on who you are writing for; there is no single correct number.
How is the Flesch Reading Ease score calculated?
Flesch Reading Ease = 206.835 − 1.015 × (words ÷ sentences) − 84.6 × (syllables ÷ words). Shorter sentences and shorter words raise the score. The companion Flesch-Kincaid Grade Level turns the same inputs into a U.S. school grade.
How does the passive voice checker work?
It flags a form of the verb "to be" (is, are, was, were, be, been, being) followed by a past participle — for example "was written" or "is being reviewed". This is the standard heuristic; it deliberately errs toward over-flagging, so each hit is shown as "possible passive" for you to judge.
Is this readability checker free and private?
Yes. It is completely free, with no signup and no word limit. All analysis runs in your own browser — your text is never uploaded, and it is saved only on your own device so it is still there when you come back.
What reading level should my writing be?
Most general-audience and online writing reads best at about a 7th- to 9th-grade level. Lower is easier to scan; higher suits specialist readers. ClearPen reports several grade formulas plus a consensus, so you are not relying on a single estimate.