Readability Score Checker
Analyse your text with Flesch, Gunning Fog, and SMOG readability scores. Free, instant, private.
Paste text to see readability scores (Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau) and the target reading age. Most web content should aim for grade 6 to 8.
Text Statistics
Writing Insights
Understanding Readability Scores
Readability formulas estimate how easy your text is to understand based on sentence length and word complexity. They were originally developed for education, figuring out which textbooks matched which grade levels. Today, they're essential for anyone writing web content, marketing copy, or documentation.
The key insight is simple: shorter sentences and simpler words are easier to read. That doesn't mean dumbing down your content, it means respecting your reader's time and attention. The best writers in the world use short sentences when they want clarity and longer ones when they want rhythm.
Score Comparison
| Score | What It Measures | Target for Web Content | How It's Calculated |
|---|---|---|---|
| Flesch Reading Ease | Overall readability (0-100 scale, higher = easier) | 60-70 (8th-9th grade) | Sentence length + syllables per word |
| Flesch-Kincaid Grade | US school grade level needed to understand | Grade 7-9 | Same inputs as Flesch Ease, different weights |
| Gunning Fog Index | Years of education needed | 8-12 | Sentence length + % of complex words (3+ syllables) |
| SMOG Index | Years of education needed (more conservative) | 8-12 | Complex words per 30 sentences |
What this means for you: Don't chase a single number. Look at the overall picture. If all four scores say "difficult", your content needs simplifying. If they disagree, focus on Flesch Reading Ease, it's the most widely used and best validated.
Flesch Reading Ease Scale
| Score | Difficulty | Grade Level | Example Content |
|---|---|---|---|
| 90-100 | Very Easy | 5th grade | Children's books, simple instructions |
| 80-89 | Easy | 6th grade | Conversational English, tabloid press |
| 70-79 | Fairly Easy | 7th grade | Most marketing copy, blog posts |
| 60-69 | Standard | 8th-9th grade | BBC News, quality newspapers |
| 50-59 | Fairly Difficult | 10th-12th grade | Business writing, trade publications |
| 30-49 | Difficult | University | Academic papers, legal documents |
| 0-29 | Very Confusing | Post-graduate | Tax law, insurance policies |
Practical Tips for Better Readability
Break Long Sentences
If a sentence has more than 25 words, consider splitting it. Find the "and" or "but" and make two sentences. Your reader's working memory will thank you.
Swap Complex Words
"Utilise" → "use". "Commence" → "start". "Approximately" → "about". Simpler words aren't less precise, they're more accessible.
Use Active Voice
"The report was written by the team" → "The team wrote the report." Active voice is shorter, clearer, and more engaging.
Vary Sentence Length
All short sentences feel choppy. All long ones feel exhausting. Mix them. A short sentence after a long one creates emphasis. Like this.
Famous Readability Examples
Hemingway, Grade 4-5
"He was an old man who fished alone in a skiff in the Gulf Stream." Short sentences, common words, concrete images. Hemingway's prose proves that simple writing isn't simple-minded, it's harder to achieve than complexity.
The Sun, Grade 6-7
Britain's best-selling newspaper writes at primary school reading level. Not because readers are uneducated, but because short, punchy sentences are easier to read on a commute, on a phone, or when tired.
BBC News, Grade 9-10
The BBC editorial guidelines target a reading level accessible to most UK adults. They avoid jargon, keep sentences under 25 words, and explain technical terms on first use.
Academic journals, Grade 16+
Average sentence length of 25+ words, heavy jargon, passive voice. Necessary for precision in specialised fields, but terrible for general audiences. If your blog reads like a journal, you've lost 90% of readers.
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How to use this tool
Paste your text into the editor
View instant readability scores
Check writing insights for improvement tips
Common uses
- Checking blog post readability before publishing
- Simplifying marketing copy for wider audience reach
- Ensuring documentation meets target education level
- Comparing readability across different content versions
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Frequently Asked Questions
What readability scores are calculated?
What is a good readability score?
Is my text stored or sent anywhere?
How accurate are these scores?
What is Flesch Reading Ease?
What is the Gunning Fog Index?
What is the SMOG Index?
Why does my readability score change so much with small edits?
What makes a word 'complex' in these formulas?
Should I aim for the same readability across all content?
Can readability scores be too high (too easy)?
Do these scores work for languages other than English?
Results are for general informational purposes only and should be checked before use. They are not professional advice. See our Disclaimer and Terms of Service.