Readability Checker
Analyze your content with 6 readability formulas. Get Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, Coleman-Liau, SMOG, and ARI scores with visual gauges, grade level summaries, and actionable improvement suggestions.
How to Use This Tool
- Paste your content into the text area. Copy text from your blog post, article, web page, or marketing copy. You can also click Load Sample to try with example content.
- Click Analyze (or press Ctrl+Enter) to process the text and generate readability scores across all 6 formulas.
- Review the 6 score cards showing Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, Coleman-Liau, SMOG, and ARI. Each card shows a numeric score, color-coded gauge, and grade level label.
- Check the stats summary bar for sentence count, word count, syllable count, average words per sentence, and average syllables per word.
- Read the overall summary to see what grade level your content reads at and whether it is suitable for a general web audience.
- Follow the improvement suggestions to make your content more readable. Edit your text and re-analyze to track your progress.
About the Readability Checker
Readability formulas have been used since the 1940s to measure how easy or difficult text is to read. They were originally developed for educational purposes, helping teachers select age-appropriate reading materials for students. Today, readability analysis is essential for content marketers, UX writers, technical authors, and anyone publishing content on the web. This tool implements six of the most widely recognized readability algorithms, giving you a comprehensive view of your content's accessibility.
The Flesch Reading Ease score is the most popular readability metric. It produces a score between 0 and 100, where higher scores indicate easier reading. A score of 60-70 is considered ideal for web content, corresponding to an 8th-9th grade reading level that most adults can comfortably read. The Flesch-Kincaid Grade Level translates the same factors into a U.S. school grade level, making it intuitive to understand. If your content scores at a 12th grade level, it requires the reading ability of a high school senior.
The Gunning Fog Index specifically penalizes complex words with three or more syllables, making it particularly useful for business and technical writing where jargon tends to inflate readability scores. The Coleman-Liau Index uses character count instead of syllable count, which makes it more reliable for machine analysis since character counting is unambiguous. The SMOG Index (Simple Measure of Gobbledygook) focuses on polysyllabic words and is considered one of the most accurate formulas for healthcare and government content. The Automated Readability Index (ARI) uses characters per word and words per sentence, providing a quick computational estimate of grade level.
Readability directly impacts your content's effectiveness. Research shows that the average American adult reads at a 7th-8th grade level, and online reading comprehension is even lower due to scanning behavior. Content that is too complex leads to higher bounce rates, lower engagement, and fewer conversions. Google's helpful content update emphasizes people-first content, and readable writing is a core component of user satisfaction. While readability is not a confirmed direct ranking factor, its effect on user engagement metrics like dwell time and bounce rate makes it an indirect SEO signal.
For marketing copy, aim for a Flesch Reading Ease score of 65 or higher. Use short sentences, common words, active voice, and clear structure. Break long paragraphs into digestible chunks. Use subheadings and bullet points to aid scanning. Everything in this tool runs 100% in your browser with no data sent to any server. Your content stays private, and your text is auto-saved locally so you can return and continue editing anytime.
Frequently Asked Questions
What is a readability score?
A readability score is a numerical measure of how easy or difficult a piece of text is to read. Scores are calculated using mathematical formulas that analyze factors like sentence length, word length, and syllable count. Common readability formulas include Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog Index, Coleman-Liau Index, SMOG Index, and Automated Readability Index (ARI).
How does the Flesch Reading Ease scale work?
The Flesch Reading Ease scale ranges from 0 to 100, where higher scores mean easier reading. A score of 90-100 is very easy (5th grade), 80-89 is easy (6th grade), 70-79 is fairly easy (7th grade), 60-69 is standard (8th-9th grade), 50-59 is fairly difficult (10th-12th grade), 30-49 is difficult (college level), and 0-29 is very difficult (graduate level). Most web content should aim for 60-70.
What is the ideal readability for web content?
For web content, aim for a Flesch Reading Ease score between 60 and 70, which corresponds to an 8th to 9th grade reading level. This ensures your content is accessible to the widest possible audience. Marketing copy and blog posts should be even simpler (70+), while technical documentation may be lower (50-60). The average American reads at a 7th-8th grade level.
How can I improve my content's readability?
To improve readability: (1) shorten sentences to under 20 words on average, (2) use simple, common words instead of complex jargon, (3) break long paragraphs into shorter ones, (4) use active voice instead of passive voice, (5) replace multi-syllable words with simpler alternatives, (6) use bullet points and subheadings to break up text, and (7) read your content aloud to catch awkward phrasing.
What is the difference between Flesch-Kincaid and Gunning Fog?
Both formulas estimate grade level, but they use different factors. Flesch-Kincaid Grade Level considers average sentence length and average syllables per word. Gunning Fog Index considers average sentence length and the percentage of complex words (words with 3 or more syllables). Gunning Fog tends to give slightly higher grade levels because it specifically penalizes multi-syllable words, which are common in business and technical writing.
What counts as a syllable in readability formulas?
A syllable is a unit of pronunciation having one vowel sound. For readability calculations, syllables are typically counted by identifying vowel groups (a, e, i, o, u, and sometimes y) in each word. Silent "e" at the end of words is usually not counted. For example, "marketing" has 3 syllables (mar-ket-ing), "the" has 1, and "communication" has 5 (com-mu-ni-ca-tion). Every word has at least 1 syllable.
Does readability affect SEO?
While Google has not confirmed readability as a direct ranking factor, it indirectly affects SEO through user engagement metrics. Content that is easier to read tends to have lower bounce rates, higher time on page, and better engagement. Google's helpful content update emphasizes content written for people, and readable content satisfies user intent more effectively. Many SEO tools like Yoast recommend targeting a Flesch Reading Ease score of 60 or higher.
What reading level should marketing copy target?
Marketing copy should target a 6th to 8th grade reading level (Flesch Reading Ease of 65-80). This makes your message accessible to the broadest audience. Successful brands like Apple, Nike, and Coca-Cola use simple, direct language in their marketing. Even when targeting educated professionals, simpler writing performs better because people skim online content. Headlines should be even simpler than body copy.