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HomeSEO ToolsReadability Score

Readability Score — Flesch & Fog Checker

Analyze text readability with Flesch-Kincaid, Gunning Fog, and other industry-standard scores.

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How to Use

  1. 1Paste or type your text into the input area.
  2. 2Read the three scores that update as you type: Flesch Reading Ease (higher = easier), Flesch-Kincaid Grade Level, and Gunning Fog Index.
  3. 3For web content targeting general audiences, aim for Flesch Reading Ease above 60 and FK Grade Level of 6–8.
  4. 4Check the stats breakdown to identify what is driving your score: very long sentences inflate grade level, and complex words (3+ syllables) inflate the Gunning Fog Index.
  5. 5To improve your score, split the longest sentences first — breaking one 35-word sentence into two is usually the fastest way to lower grade level.
  6. 6Replace or define complex words (e.g., 'utilize' → 'use', 'approximately' → 'about') to reduce the Fog Index without losing meaning.

About Readability Score

The Readability Score tool calculates three industry-standard metrics: Flesch Reading Ease (0–100, higher is easier), Flesch-Kincaid Grade Level (US school grade equivalent), and Gunning Fog Index (years of education needed to understand the text).

Content creators and SEO professionals use readability scores to optimize for their target audience. Blog posts typically aim for Grade 6–8 (easily understood by most adults). Marketing copy targets Grade 5–7. Academic and technical writing ranges from Grade 12 to 17+.

The stats panel breaks down total words, sentences, syllables, and complex words (3+ syllables) so you can identify what is driving your score. Simplify long sentences and replace complex words to improve readability without losing meaning.

Frequently Asked Questions

What is the Flesch Reading Ease score?

A score from 0 to 100. Higher means easier: 90–100 is 5th grade level, 60–70 is standard (8th–9th grade), and below 30 is very difficult (academic/technical).

What is the Flesch-Kincaid Grade Level?

It estimates the US school grade needed to understand the text. Grade 8 is accessible to most adults. Grade 12+ is college-level. Grade 6–8 is ideal for web content.

What is the Gunning Fog Index?

It estimates years of formal education needed. A score below 12 is accessible to most readers. 17+ indicates academic or highly technical writing.

What counts as a complex word?

Words with 3 or more syllables are counted as complex in the Gunning Fog calculation. Reducing complex words is the fastest way to lower your Fog score.

What readability level should I target for SEO?

For web content and blog posts, aim for Flesch Reading Ease above 60 (Grade 6–8). Google has shown preference for content that is accessible to a wide audience.

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