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📖 Free Readability Checker

Free Readability Checker — Flesch Score, Grade Level & Fixes

Paste your text to get the Flesch Reading Ease score, four grade-level formulas, and sentence-by-sentence highlights for long sentences, passive voice and hard words — with a plain-English list of what to fix. Free, instant and private.

✓ 100% Free ✓ No Signup Required ✓ 5 Readability Formulas ✓ Sentence Highlighting ✓ Runs in Your Browser
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Flesch Reading Ease
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Average Grade Level
Flesch-Kincaid Grade
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US school grade. Aim for 8 or below for the web.
Gunning Fog Index
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Years of education needed. Under 12 is ideal.
SMOG Index
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Based on 3+ syllable words. Under 10 reads easily.
Coleman-Liau Index
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Based on letters per word. Under 10 is easy.
Avg Words per Sentence
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15–20 is comfortable for most readers.
Long Sentences (20+ words)
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Keep under 25% of sentences.
Passive Voice
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Keep under 10% of sentences.
Hard Words (3+ syllables)
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Under 12% of words keeps text light.
Very long (30+ words) Long (21–29 words) Passive voice Hard word
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Words
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Sentences
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Paragraphs
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Reading Time
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-ly Adverbs

How Our Free Readability Checker Works

Three steps — no account, no waiting.

1

Paste Your Text

Any blog post, web page, email or essay. 100+ words gives the most reliable scores.

2

Pick Your Audience

Choose who you’re writing for, and the checker judges your score against the right target.

3

Fix What’s Flagged

See your scores, a list of fixes and every long, passive or hard sentence highlighted in place.

What Each Readability Score Means

Five standard formulas, explained in plain English.

📏

Flesch Reading Ease (0–100)

Higher is easier. 60–70 is plain English that most adults read comfortably; 30 or below reads like an academic paper. It’s based on sentence length and syllables per word.

🎓

Flesch-Kincaid Grade

The same inputs as a US school grade. Grade 8 means a 13–14-year-old could follow it — a good target for most web content.

🌫️

Gunning Fog & SMOG

Both focus on long words with three or more syllables. They rise quickly in jargon-heavy text, so they’re a good check for technical and business writing.

🔤

Coleman-Liau Index

Uses letters per word instead of syllables, so it doesn’t depend on syllable counting. When the formulas disagree, look at the average grade.

Why Use BrightlyFuture’s Readability Checker

More than a score: it shows you what to change.

🔓

Free, No Limits

No signup, no word caps, no daily limits.

🎯

Audience Targets

Judges your score against blog, public, business or academic readers instead of one fixed number.

🔎

Sentence Highlighting

Long sentences, passive voice and hard words are marked in your text, so you know exactly where to edit.

🔧

Plain-English Fixes

A short list of the changes that will raise your score most, based on your actual text.

🔒

100% Private

Everything runs in your browser. Your text is never uploaded or stored.

📄

Free Reports

Copy or download a report with every score, fix and flagged sentence.

Who Uses Our Readability Checker?

Anyone who wants to be understood the first time.

💻

Bloggers

Keep posts easy to skim so readers stay on the page.

💼

SEO Professionals

Check client content and briefs against a clear readability target.

🏢

Businesses

Make product pages, emails and policies clear to customers.

🎓

Students

Spot overlong sentences and heavy jargon before you submit.

✍️

Writers & Editors

Find the exact sentences that slow readers down.

🤖

AI-Assisted Writers

AI drafts often score low; see which sentences to shorten.

How to Improve Your Readability Score

The changes that move the score most.

1

Split Long Sentences

Sentence length has the biggest effect on every formula. Break anything over 25 words at “and”, “but” or “which”.

2

Swap Long Words for Short Ones

“Use” not “utilise”, “help” not “facilitate”, “about” not “approximately”.

3

Write in the Active Voice

“We updated the page” beats “The page was updated by us”. It’s shorter and clearer.

4

Keep Paragraphs Short

Two to four sentences per paragraph makes text easier to scan on a phone, even though formulas don’t measure it.

5

Don’t Chase the Score

Formulas can’t judge meaning. Keep the technical terms your readers need. Read our full guide on how to improve your blog readability score.

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Done-for-you

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Our team writes and edits content that reads easily and is built around what your customers search for.

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Frequently Asked Questions About Readability

Everything you need to know about readability scores.

For most blogs and web pages, 60–70 is a good target: plain English that most adults read easily. Content for a wide public audience can aim for 70+, while business and technical writing often sits at 40–60.

Yes. No signup, no word limit and no daily cap.

No. All the calculations run in your browser. Your text never leaves your device.

Each formula weighs different things: syllables, letters per word or long words. They usually land within a couple of grades of each other. The average grade in the second ring smooths out the differences.

Google doesn’t use a readability score as a ranking factor. But clear writing helps readers find answers and stay on the page, which is what Google’s helpful content guidance is about.

The checker looks for a form of “to be” followed by a past participle, such as “was written” or “is being tested”. It catches most cases but can miss irregular verbs or flag adjectives, so treat it as a pointer.

Each line break is treated as the end of a sentence, so short headings and list items lower the average sentence length and raise the score. For the most accurate reading, check your body paragraphs.

Syllables are counted with standard English rules rather than a dictionary, the same approach most readability tools use. It’s accurate for most words but can be off by one on unusual ones, which barely changes the overall score.

No. These formulas were designed for English and the syllable rules are English-only.

Words like “really”, “extremely” or “quickly”. A few are fine, but many often signal weak verbs. The count is a prompt to check, not a rule.

Yes. Copy Report or Download Report gives you every score, the list of fixes and each flagged sentence as plain text.

How Readable Is Your Writing?

Find out in seconds — free, private and instant.

No Signup · 5 Formulas · Sentence Highlights · Free Reports
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