Readable writing is not dumbed-down writing. It is writing that a busy reader can follow on the first pass, without re-reading a sentence to work out where it ends. On the web, where people skim and skip, that first-pass clarity is most of the battle. Readability scores give you a rough, useful gauge of how hard your writing is to follow — and, more helpfully, they point at the two things you can actually change.
What the Flesch score measures
The Flesch Reading Ease score runs from roughly 0 to 100. Higher is easier. It is built from just two inputs: your average sentence length, and your average number of syllables per word. Shorter sentences and shorter words push the score up; long sentences and long words push it down. That is the whole mechanism, and its simplicity is the point — it measures the two levers that most affect reading difficulty.
- 90–100: very easy, roughly a fifth-grade reading level.
- 60–70: plain English, comfortable for most adults — a good target for general web copy.
- 30–50: fairly difficult, the register of much academic and corporate writing.
- 0–30: very difficult, best reserved for specialist readers.
The related Flesch–Kincaid grade level reframes the same maths as a US school year. A grade level of 8 means the text suits a reader in the eighth grade. For public-facing web copy, aiming somewhere around grade 7 to 9 keeps the writing accessible without sounding childish.
ReadabilityPaste a draft to see the reading-ease score and grade level update live as you shorten sentences and swap in plainer words.What the score cannot see
A readability score is a proxy, not a judge. It counts syllables and sentence lengths; it does not understand meaning. You can write a perfectly clear sentence that scores badly because it happens to use a few long technical terms, and you can write incoherent nonsense that scores well because every word is short. Jargon that a formula reads as “easy” may be opaque to your actual reader.
So treat the number as a smoke alarm, not a grade. A sudden drop tells you a passage has become dense and worth a look. It never tells you the writing is good. Read the passage aloud; if you run out of breath before the full stop, the sentence is too long regardless of the score.
Sentence length is the biggest lever
Of the two inputs, sentence length is the one you have most control over and the one that most affects a reader. For web copy, an average of 15 to 20 words per sentence reads comfortably. The trouble is rarely the average, though — it is the outliers. One 45-word sentence buried in a paragraph of short ones is where a reader stalls, even if the average looks fine.
Vary your lengths deliberately. A run of sentences that are all the same length reads flat and mechanical. Mix short and medium sentences, and use the occasional very short one to land a point. Find the longest sentences and ask, of each, whether it is carrying two ideas that would be clearer as two sentences.
Sentence CounterCheck the average sentence length and scan the longest sentences to find the ones worth splitting.Words: shorter usually wins
The second lever is word length, and the rule is simple: prefer the shorter, plainer word when it means the same thing. “Use” beats “utilise”. “Buy” beats “purchase”. “Help” beats “facilitate”. This is not about banning long words — some ideas need a precise, longer term — but about not reaching for the grand version out of habit.
- Cut filler openers: “it is important to note that”, “in order to”, “the fact that”.
- Prefer active voice: “we tested the tool” over “the tool was tested”.
- Choose a concrete noun over an abstract one where you can.
- Delete adverbs that add nothing: “very”, “really”, “quite”, “actually”.
A workflow that actually helps
Write your draft first without watching the score — chasing a number while drafting produces stilted prose. Once the argument is on the page, run it through a readability check and look at the grade level and the longest sentences together. Fix the outliers, swap the obviously grand words for plain ones, then re-read the whole thing aloud. The aim is a score in a sensible band and, more importantly, a piece that reads cleanly on the first pass.
The scoring happens in your browser as you type, so unpublished copy — a launch announcement, a client draft, an internal memo — is not sent anywhere to be measured. You get the feedback live without the text leaving the page.