Readability Checker
Paste any text and get Flesch Reading Ease, Gunning Fog Index, and grade-level scores in one click.
Free, no sign-upUpdated
Use the tool
Results update automatically as you type.
How it works
- • Flesch Reading Ease: 0 to 100. Above 60 is readable for most adults
- • FK Grade Level: US school grade needed to understand the text
- • Results update automatically as you type, no submit needed
What gets measured
Four scores, each measuring a different dimension of complexity:
- Flesch Reading Ease: 0 to 100. Above 60 is readable for most adults
- Flesch-Kincaid Grade Level: US school grade needed to understand the text
- Gunning Fog Index: combines sentence length and complex word count
- Average sentence length and syllables per word
The target most SEO content misses
Flesch Reading Ease below 30 is classified as "Very Confusing": the level of academic research papers. Most top-ranking informational content scores 60–70.
How to use it
- Paste your draft or a section of it into the text area
- Check the Flesch Reading Ease score first: it's the most actionable
- If the score is low: break long sentences, replace multi-syllable words where shorter ones work
- Paste again after editing to confirm the improvement
Target scores by content type
General SEO content: aim for Flesch 60–70, grade level 8–9. Product documentation: 50–60 is acceptable. Technical developer docs: 40–50 is fine if the audience expects it. Anything below 30 loses most readers before they finish the page.
Frequently asked questions
Is this readability checker free?
Yes, free and no signup. Paste text and get the scores instantly.
What readability score should I aim for?
For general web content, a Flesch Reading Ease in the 60 to 70 range, roughly grade 7 to 9, works well.
Does readability affect SEO?
Not as a direct ranking factor, but it improves engagement and comprehension, which support rankings indirectly.
Related tools: keyword density checker and meta tags analyzer. Background reading: balancing SEO and natural content.