Measure the readability of any page: Flesch Reading Ease (0–100), Flesch-Kincaid grade level, average sentence length and complex-word share. Easier copy keeps readers (and converts) better — this shows where to simplify.
⚡ Interactive demo — sample data
Reading ease 52/100 (fairly difficult) — about a grade 11 reading level. Long sentences and jargon are dragging it down.
Flesch Reading Ease: 52/100 — fairly difficult. Below the 60+ plain-English target for general web copy.Warning
Grade level (Flesch-Kincaid): Grade 11.2 — reads like late high school; aim for grade 7–9 for a broad audience.Warning
Avg. words per sentence: 27.4 — well over the ~20-word guideline. Splitting the longest sentences is the biggest quick win.Warning
Complex words (3+ syllables): 24% — jargon and formal vocabulary above the ~20% comfort line.Warning
Scored 640 words across 23 sentences — plenty of text for a reliable result.Looks good
Main content detected and measured — menus, header and footer were excluded from the score.Looks good
Measure the readability of any page: Flesch Reading Ease (0–100), Flesch-Kincaid grade level, average sentence length and complex-word share. Easier copy keeps readers (and converts) better — this shows where to simplify.
How it works
Enter your page URL
Paste any public URL and run the check. We fetch the page and pull out its main readable text — the body copy inside the main content area, with navigation, headers, footers, scripts and styling stripped out — so the score reflects what a reader actually reads, not boilerplate.
Read your scores
You get the Flesch Reading Ease score (0–100), the Flesch-Kincaid grade level, your average words per sentence, and the share of complex (3+ syllable) words. Each number is plain-labeled and flagged green, amber or red so you can see at a glance whether the copy is easy or a slog.
Simplify and re-run
Shorten the longest sentences, swap jargon for everyday words, and break dense paragraphs up. Run the check again — when Reading Ease climbs toward 60+ and the grade level drops toward 7–9, your copy is hitting the sweet spot for a broad web audience.
What we check
Flesch Reading Ease (0–100) — A 0–100 score where higher is easier. Roughly: 90–100 is very easy (5th grade), 70–79 easy, 60–69 plain English (~8th–9th grade), 30–49 difficult, and under 30 very difficult. Most web copy should aim for 60 or above. The math rewards shorter sentences and shorter words.
Flesch-Kincaid grade level — The same inputs expressed as a US school grade — a 9.0 means a typical 9th grader can read it. We flag grade 9 and under as good, 10–13 as a caution, and above 13 (college level) as too hard for general audiences. Most web pages should target grade 7–9.
Average words per sentence — Long sentences are the single biggest driver of a low score. We measure your average sentence length and flag anything over ~20 words. Aiming for under 20 — with a mix of short and medium sentences — is the fastest way to make a page easier to read.
Complex-word share (3+ syllables) — The percentage of your words that have three or more syllables. A high share usually means jargon, abstract nouns, or needlessly formal vocabulary. We flag a page when more than ~20% of words are complex.
Word and sentence counts — We show the total words and sentences we scored so you can sanity-check the result. Very short pages (under ~30 words of body text) can't be scored reliably, so we tell you instead of returning a misleading number.
Main content only — We score the page's primary text — the article or main region — not the menus, cookie notices, or footer links. That keeps boilerplate from skewing the score and gives you a number that reflects the copy you actually wrote.
Common issues we catch
Sentences that run too long — The most common cause of a low score. A 40-word sentence packed with clauses tanks both Reading Ease and grade level. Split it into two or three shorter sentences and the score jumps — no vocabulary change needed.
Jargon and abstract vocabulary — Words like 'utilize,' 'facilitate,' 'leverage,' and 'optimization' are multi-syllable and inflate the complex-word share. Swapping them for 'use,' 'help,' and 'improve' makes the page measurably easier and usually clearer too.
A great score that reads badly anyway — Flesch is a math formula counting syllables and sentence length — it can't judge whether your writing is logical, accurate or persuasive. A page can score 75 and still be vague. Use the score as a clarity check, not a substitute for editing.
Industry copy that has to use hard words — Legal, medical and technical pages naturally score lower because the subject demands long, specialist terms. That's expected — for those audiences a grade 11–13 score can be appropriate. Match the target reading level to who's actually reading, rather than forcing every page to 60+.
Thin pages that can't be scored — Landing pages with a headline and a button may have too little body text (under ~30 words) for a stable score. The fix isn't gaming the formula — it's adding genuinely useful copy that answers the visitor's question.
Text locked inside images or scripts — If your main copy is baked into an image or only rendered by JavaScript after load, it may not be in the HTML we read, so the score covers less text than you expect. It's also a problem for search engines and screen readers — put real text in the page.
Treating readability as a direct ranking factor — There is no documented Google ranking factor called 'Flesch score.' Readability helps indirectly — easier pages keep readers longer, are more accessible, and convert better. Don't sacrifice accuracy or completeness just to hit a number.
Where this matters
Blog posts & articles — Long-form content is where readability matters most. A plain-English score keeps readers scrolling instead of bouncing, and makes your key points skimmable — both of which help the page earn its time on screen.
Landing & sales pages — Conversion copy lives or dies on clarity. Easy-to-read headlines and benefit statements remove friction at the moment a visitor decides whether to act, which is why most high-converting pages read at a grade 6–8 level.
WCAG / accessibility audits — WCAG's Success Criterion 3.1.5 (Reading Level, AAA) explicitly references lower-secondary reading level. Clear, plain copy is a recognized accessibility practice that helps readers with cognitive and language differences, not just convenience.
WordPress, Shopify & CMS editors — Many editors (and SEO plugins) surface a readability score while you write. This tool lets you check any live page — including ones built outside your CMS — against the same well-known Flesch formulas, so the numbers line up.
Email, docs & UX microcopy — The same Flesch and Flesch-Kincaid scores apply to any prose — newsletters, help docs, button and form copy. Paste the live page and you get a consistent benchmark you can apply across every surface a customer reads.
Frequently asked questions
What is a good Flesch Reading Ease score?
For general web audiences, aim for 60 or above — that's the 'plain English' band, readable by most adults at around an 8th-to-9th-grade level. Marketing and blog copy often does best in the 60–70 range. Technical or specialist pages will score lower, and that can be fine for their audience.
How is the Flesch Reading Ease score calculated?
It's a formula based on two things: your average sentence length (words per sentence) and your average word length (syllables per word). Shorter sentences and shorter words push the score up; long sentences and big words push it down. It produces a number from 0 (very hard) to 100 (very easy).
What's the difference between Reading Ease and grade level?
They use the same inputs but express the result differently. Reading Ease is a 0–100 score where higher is easier. Flesch-Kincaid grade level converts that into a US school grade — a 9.0 means a typical 9th grader can read it. We show both so you can pick whichever framing is clearer for you.
What counts as a complex word?
We count a word as complex if it has three or more syllables. A high share of complex words usually points to jargon or overly formal vocabulary. Bringing that share under about 20% — by swapping in shorter, everyday words — is one of the quickest ways to improve a score.
Does readability affect my Google rankings?
Not directly — there's no published Google ranking factor named 'Flesch score.' The benefit is indirect but real: easier pages keep readers engaged, are more accessible, and convert better, all of which support how a page performs. Treat readability as a UX and clarity signal, not an SEO cheat code.
Why is my page's score lower than I expected?
The usual culprits are long sentences and multi-syllable words — both weigh heavily in the formula. Check your average words per sentence first; if it's over 20, splitting sentences will move the score more than anything else. After that, look at the complex-word share for jargon to simplify.
Can a page score well but still read poorly?
Yes. Flesch only measures sentence and word length — it can't tell whether your writing is accurate, well-organized, or persuasive. A page can score 75 and still be confusing. Use the score as a guardrail, then edit for substance and flow on top of it.
How much text do I need for an accurate score?
Roughly 30 words of body copy at minimum; the more, the more stable the result. Very short pages — a headline and a button — don't give the formula enough to work with, so we'll tell you there isn't enough text rather than return a misleading number.
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