Flesch Reading Ease Explained: How to Write for Any Audience
That readability score under your word count isn't just a number — it's a formula from 1948 that's still one of the fastest ways to check if your writing is actually easy to read.
Key takeaways
- The Flesch Reading Ease formula, from 1948, measures sentence length and word length — nothing else.
- Higher score = easier to read. 60-70 is standard, general-audience writing; below 30 is dense and academic.
- Shortening sentences moves the score faster than swapping individual words.
- It's a proxy for reading effort, not a verdict on whether writing is good or clear.
- Not everything should aim for a high score — technical and legal writing has different, valid conventions.
The 1948 formula that's still in Microsoft Word
Rudolf Flesch published his Reading Ease formula in 1948 — and nearly eighty years later, it's still built into Microsoft Word, still shows up in SEO tools, and is still required reading for U.S. government plain-language guidelines. That's an unusually long shelf life for a piece of math from the 1940s.
What it actually measures is narrow: sentence length and word length. Longer sentences and longer, multi-syllable words push the score down (harder to read); short sentences with short, common words push it up (easier to read). It's not measuring whether your writing is good, clear, or correct — a formula can't judge that. It's a proxy for one specific thing: how much effort the average reader needs to parse your sentences on a first read.
How to read the number
The scale runs roughly from 0 to 100, and higher means easier to read.
- 90-100 — very easy, roughly 5th-grade level (children's books)
- 60-70 — standard, plain writing, roughly 8th-9th grade (a common target for web content)
- 30-50 — fairly difficult, more formal writing
- Below 30 — difficult, dense, academic-style (legal documents, research papers)
Two levers, and only one moves the needle fast
The formula only cares about two things, so there are really only two levers: shorten your sentences, and use shorter, more common words where you can.
A useful editing pass: find your longest sentences first and look for a natural place to split them into two. Then look for any unnecessarily formal word choice — "utilize" instead of "use", "prior to" instead of "before" — and swap it for the plainer version. Neither change requires dumbing down your ideas, just the sentence structure carrying them.
“A single 40-word sentence stuffed with three ideas does more damage to your score than a handful of long words scattered through short sentences.”
When a lower score is actually the wrong goal
Not everything should aim for a 70. A legal disclaimer, a technical API reference, or an academic paper has its own audience and its own conventions, and forcing those into short, simple sentences can make them less precise or less credible to the readers they're written for.
It's also just one signal, not a verdict. A passage can score well and still be unclear if it's poorly organized, or score poorly and still be perfectly fine for its intended, more technical audience. Treat it as a nudge to reconsider your longest sentences, not a grade to chase for its own sake.
Check your own writing
Open Tools Library's Word Counter calculates both the Flesch Reading Ease score and the Flesch-Kincaid Grade Level live as you type or paste in a draft, alongside word count, sentence count, and a keyword density breakdown for anyone checking SEO content. Nothing you paste in is uploaded anywhere — the whole thing runs in your browser.
Mentioned in this post
Word Counter
Count words, characters, sentences, and paragraphs live as you type, plus get a Flesch readability grade and a stopword-filtered keyword density report.
Case Converter
Convert text into 14 case formats simultaneously — UPPERCASE, Title Case, camelCase, snake_case, kebab-case, and more — each with its own instant copy button.
Frequently asked questions
What's a good Flesch Reading Ease score for a blog post?
Most general-audience web content aims for 60-70 — plain, standard writing that's easy to skim without feeling dumbed down.
Is a higher score always better?
Not for every audience. Technical, legal, or academic writing often needs precision that short, simple sentences can't carry — a lower score there isn't a problem to fix.
What's the difference between Reading Ease and Grade Level?
Same underlying math, different scale. Reading Ease runs 0-100 (higher = easier); Grade Level maps to a U.S. school grade (lower = easier).
Does shortening words help more than shortening sentences?
Sentence length moves the score faster in most real writing — a long, multi-clause sentence does more damage than a few long words spread through short sentences.