Readability Score Checker
A readability score checker estimates how easy an English text is to read. Paste your text and this free tool counts sentences, words and syllables and calculates six common scores, including Flesch Reading Ease and Flesch-Kincaid Grade. It shows every formula and the sentences that are longest, so you know what to shorten.
This tool checks the HTML you paste. It does not visit your page, run your scripts or see your CSS.
Readability Index Estimates & Formulas:
Formula: 206.835 - 1.015 × (words/sentences) - 84.6 × (syllables/words)
Formula: 0.39 × (words/sentences) + 11.8 × (syllables/words) - 15.59
Formula: 0.4 × ((words/sentences) + 100 × (complex words/words))
Formula: 1.043 × √(complex words × 30 / sentences) + 3.1291
Formula: 0.0588 × L - 0.296 × S - 15.8 (L = letters/100 words, S = sentences/100 words)
Formula: 4.71 × (characters/words) + 0.5 × (words/sentences) - 21.43
| Rank | Word Count | Sentence Text |
|---|
What is a readability score checker and when should you use it?
Readability formulas turn sentence length and word length into a number. Shorter sentences and shorter words give an easier score. The scores are rough guides for English and can't judge whether your text is clear or useful. Count repeated words with the Keyword Density Checker, check your document outline with the Heading Structure Checker, measure headline lengths with the Title Tag Length Checker, or review descriptions with the Meta Description Length Checker.
How do you use it?
- Paste your English text.
- Press Check.
- Read the scores and the longest sentences.
- Shorten the sentences that are hardest to read.
Working on a comprehensive technical audit? Browse all free SEO tools to discover the next step in your workflow, or contact our technical support team if you require a specialized custom utility.
Result interpretation & practical applications
When evaluating the output of the readability score checker, review the parsed metrics against your specific site architecture. Outputs are formatted for direct implementation into your HTML source, web server configuration, or Google Search Console audit files.
Always inspect generated values for contextual nuance. Automated tools highlight structural patterns, but manual verification confirms that technical directives align with your overarching SEO strategy.
Technical rules and limitations
- Each score uses its published formula, shown next to the result.
- Syllable counts in English are estimated, so scores are estimates.
- SMOG needs at least 30 sentences.
For writing that serves readers, see Google's guide to creating helpful, reliable, people-first content and the federal Plain Language guidelines.
Common mistakes and troubleshooting
- Chasing a score instead of clarity.
- Scoring text that includes menus and footers.
- Using the tool for languages other than English.
No tool can promise how a search engine will crawl, index, or rank your pages. This tool generates and validates code against documented technical specifications; you determine where to deploy it, and you should always test changes on staging environments first. Google publishes extensive guidelines in Search Central on evaluating third-party SEO tools and advice. Learn more about our technical testing standards on our about us page, or explore full site audits on our pricing page.
Related free tools & workflows
Browse all Advanced On-Page SEO Tools →Technical SEO Audit Workflows
Indexability & Crawling
Redirects & HTTP Headers
Authoritative Technical Documentation & Standards
This tool executes logic aligned with official technical documentation and search engine webmaster standards:
- Google Search Central helpful content guidelines
Google Search Central: Creating Helpful, People-First Content
Primary engineering source and technical documentation.
- W3C WCAG Readability guidelines
W3C Web Accessibility Initiative: Clear and Understandable Content
Primary engineering source and technical documentation.
Readability Score Checker questions
What score should I aim for? ↓
This tool doesn't set a target. Use the scores to compare drafts.
Does Google use readability scores? ↓
This tool makes no such claim.
Can it score Bengali? ↓
No. The formulas are for English text.
Is this tool free? ↓
Yes. It is completely free to use and requires no registration or subscription.
Does this tool visit my website or store my files? ↓
No. It executes entirely in your local browser runtime. Your inputs and results are never stored or logged on our servers.
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