Updated 6th November 2026. First published in 2022.
Every article we write for a client gets a readability check before it goes out.
Not because a score decides whether writing is good. Because it's the quickest way to spot sentences that make readers work harder than they should.
The Flesch reading ease score is thbest-knownwn of these checks. This guide explains how it works, what score to aim for, whether it affects SEO and the tools I use on client work today.
What is the Flesch reading ease score?
The Flesch reading ease score rates how easy a piece of English is to read, on a scale that runs roughly from 0 to 100. The higher the score, the easier the text.
Rudolf Flesch created it in 1948. It looks at two things only, how long your sentences are and how many syllables your words have.
The formula is 206.835 − (1.015 × average sentence length) − (84.6 × average syllables per word).
Average sentence length is the number of words divided by the number of sentences. Average syllables per word is the number of syllables divided by the number of words.
Short sentences and short words push the score up. Long sentences full of long words pull it down.
| Score | Reading difficulty | US school grade |
|---|---|---|
| 90 to 100 | Very easy | 5th grade |
| 80 to 90 | Easy | 6th grade |
| 70 to 80 | Fairly easy | 7th grade |
| 60 to 70 | Standard | 8th or 9th grade |
| 50 to 60 | Fairly difficult | 10th to 12th grade |
| 30 to 50 | Difficult | College |
| 0 to 30 | Very difficult | College graduate |
Score bands from Flesch's original scale, as set out by Yoast.
You'll also see the Flesch-Kincaid grade level, a version developed for the US Navy in 1975. It uses the same two measures and gives a US school grade instead of a score. A grade of 8 means a typical 13 to 14-year-old could follow the text.
Readable, one of the main readability tools, recommends aiming for grade 8 for content written for the general public.
Flesch reading ease for SEO, does it matter?
Not directly. Google has never said it uses Flesch scores, and there's no evidence that it does.
Even Yoast, which made the score famous among WordPress users, removed it from its readability analysis, replacing it with separate checks on word complexity and sentence length.
Readability still matters for SEO, however, through what it does for readers.
Google's ranking systems reward content written for people, and clear writing is part of that. AI tools such as ChatGPT and Google's AI Overviews also quote clear, direct answers far more readily than dense paragraphs.
Readability affects sales too. Unbounce analysed more than 41,000 landing pages and found that copy written at a 5th to 7th grade reading level converted at 11.1%, about twice the rate of copy written at a professional level. It's one reason the line between SEO content writing and copywriting has blurred.
Who you're really writing for
It's easy to assume your readers read the way you do. Many don't.
The latest international adult skills survey found that 28% of US adults read at Level 1 or below in 2023, up from 19% in 2017. The share reading at Level 3 or above fell from 48% to 44%.
More US adults now struggle with complex text
Share of US adults by literacy level, PIAAC adult skills survey
Source: NCES, 2023 PIAAC results, released December 2024.
That doesn't mean your buyers can't read complex material. It means even capable readers prefer not to work hard on a website, especially on a phone.
UK public services set an even plainer standard. Surrey County Council, following GOV.UK's content design guidance, aims for its web pages to have a reading age of 9 and sentences under 20 words.
Should you increase your readability score?
Your target depends on who you're writing for. As a rule of thumb, aim for 60 to 70 for most web content.
US consumers. Aim higher, at 70 or more. Hemingway's default target is grade 9, the average reading level for US adults.
B2B and technical buyers. 50 to 60 is fine. Specialist terms lower the score, and your readers expect them.
Readers in their second language. Keep it plain. Nordic and DACH buyers often read English very well, yet plain English still saves them effort.
The Flesch-Kincaid grade level scale
US school grade needed to follow a text easily
Grade 8 target recommended by Readable for the general public.
There's a limit, though. Chase the score too hard and you end up with a string of short, choppy sentences.
That can feel patronising to an intelligent reader. I'd rather keep a slightly longer sentence that flows than break it into three that don't.
The readability tools I use
On client work, I use Hemingway and Grammarly together, and each has its place.
| Tool | Best for | Watch out for |
|---|---|---|
| Hemingway | Writing for US audiences, and spotting long, hard sentences | It pushes prose towards short sentences that can feel patronising |
| Grammarly | Every major variety of English, active voice and catching common AI writing patterns, plus checks in French, German, Spanish, Italian and Portuguese | Accept its suggestions selectively, or your voice gets flattened |
| Yoast | A solid all-round SEO check on WordPress sites | Its readability analysis is light, and no longer uses the Flesch score |
Hemingway is great for US clients, because it matches how most Americans prefer to read online. For British English, I prefer Grammarly.
Grammarly is also useful for spotting the patterns AI writing tools fall into, the stock phrases and rhythms readers now recognise. When it flags them, I rewrite those passages by hand. That's part of how we keep human input in every article, even when we use AI to draft.
How to improve your readability score
Keep paragraphs short
Online, two or three sentences is plenty for most paragraphs. Short paragraphs don't change your Flesch score, yet they make a page far easier to scan, especially on a phone.
Clear headings and subheadings do the same job. They let readers jump to the part they need.
Check what type of words you've used
Use active verbs and cut the words that don't earn their place. "We reviewed the contract" beats "the contract was reviewed by our team".
You'll be surprised how much clearer an article becomes once you remove unnecessary words.
Shorten sentences
You can cram as much information as possible into a sentence like this one, which keeps going long after the reader has lost track of where it started. It's a perfect way to lose them.
Keep most sentences under 20 to 25 words, and vary the length so the writing doesn't feel mechanical.
Keep it straightforward
Too many writers fall into the trap of being impressed by their own vocabulary. Use "small" instead of "minuscule", or "idea" instead of "concept".
Plain words aren't dumbed down. They let readers focus on what you're saying, not how you're saying it.
Write for your audience
Every rule here bends. You're writing for real people, not an algorithm or a score.
If your readers are engineers, lawyers or doctors, write the way they talk. If they're busy buyers on a phone, get to the point. Choosing between British and American English is part of the same decision.
The Flesch reading ease score is a helpful guide, not a rule. Used well, it makes your writing clearer without making it simpler than your readers deserve.
Our content writing team checks readability on every article, alongside SEO. We also work across PPC, social media and web design, so the same clear writing runs from your ads to your landing pages.
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For most web content, 60 to 70 is a good target. That's plain English that most adults can read comfortably. Content for US consumers can aim higher, at 70 or more, while technical B2B content often scores 50 to 60 because of the specialist terms its readers expect. Treat the score as a guide, and read the text aloud to check it still flows.
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No, not as far as anyone knows. Google has never said it uses Flesch scores, and Yoast has even removed the score from its readability analysis. Readability still affects SEO indirectly, because Google rewards content written for people, AI tools quote clear answers more readily and readers stay longer on pages they can follow.
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They use the same measures, sentence length and syllables per word, and present the result differently. Flesch reading ease gives a score from 0 to 100, where higher is easier. Flesch-Kincaid grade level gives a US school grade, where lower is easier. A reading ease score of 60 to 70 roughly matches grades 8 to 9.
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Often it scores reasonably well, which is part of the problem. AI drafts tend to use predictable sentence rhythms and stock phrases that pass a readability check yet read as generic. Tools such as Grammarly can flag those patterns. The fix is a human rewrite that adds real experience, specific detail and a natural voice, not just a better score.
