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Free Readability Analyzer

Check the readability of any text. Get Flesch–Kincaid grade level, average sentence length, and concrete suggestions to make your content easier to read.

Built for bloggers, marketers, and SEOs, not academics.

What this analyzer measures

Paste any text (a draft blog post, a landing page, an email) and we'll estimate its reading grade level using the Flesch–Kincaid formula, flag the longest and most complex sentences, and suggest rewrites you can copy directly.

How to use the results

  1. Check the grade level first. Above grade 10 is a warning sign for general-audience content.
  2. Look at the long-sentence list. Splitting just three or four long sentences usually moves the score significantly.
  3. Use Polish in KoalaWriter to apply readability improvements across an entire article in one click. See the Polish feature page.

Frequently asked questions

What reading grade level should I target?

Most general-audience web content reads best at grade levels 6–9. Technical or B2B content can go higher (10–12). If you're writing for a broad consumer audience, anything above grade 10 starts to hurt time-on-page and conversion.

What is the Flesch Reading Ease score?

It's a 0–100 score where higher means easier. 70+ is plain English (most blog posts should aim here), 60–70 is acceptable, 50–60 is fairly difficult, and under 50 reads like an academic paper.

Why does sentence length matter?

Long sentences force readers to hold more context in working memory. As average sentence length climbs past ~20 words, comprehension and engagement drop sharply. Splitting long sentences is the single highest-leverage readability fix.

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