Readability Analyzer
The Readability Analyzer scores your text using six industry-standard formulas: Flesch Reading Ease, Flesch-Kincaid Grade, Gunning Fog, Coleman-Liau, SMOG, and Automated Readability Index. Shows estimated reading time, grade level, sentence complexity, syllable statistics, and identifies difficult sentences. Helps writers target the right audience reading level.
Readability Scores
Text Statistics
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What is a Readability Analyzer?
A readability analyzer evaluates how easy or difficult a text is to read by applying mathematical formulas that consider sentence length, word length, syllable count, and vocabulary complexity. This tool computes six widely used readability indices — Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog, Coleman-Liau, SMOG, and Automated Readability Index — and translates them into a school grade level and reading difficulty rating. Writers, educators, and marketers use readability analysis to ensure content matches their target audience.
How to Use This Tool
- Paste your text into the input area (minimum 100 words recommended for accurate results)
- Review the six readability scores and their corresponding grade levels
- Check the average grade level and reading difficulty label (Very Easy to Very Difficult)
- Examine text statistics: word count, sentence count, syllable count, and averages
- Identify complex words and long sentences that could be simplified
Frequently Asked Questions
What readability score should I target?
It depends on your audience. For general web content, aim for Flesch Reading Ease of 60-70 (8th-9th grade). Marketing copy and blog posts often target 70-80 (6th-7th grade). Academic papers are typically 30-50. News articles target around 65. The lower the grade level, the wider your potential audience.
How are Flesch-Kincaid and Gunning Fog different?
Flesch-Kincaid Grade Level focuses on average sentence length and syllables per word. Gunning Fog adds a 'complex word' factor, counting words with three or more syllables. Fog tends to give higher grade levels because polysyllabic words significantly increase the score, even if those words are commonly understood.
Why do different readability formulas give different scores?
Each formula weighs different text features. Flesch-Kincaid uses syllables and sentence length. Coleman-Liau uses character count instead of syllables. SMOG focuses on polysyllabic words. ARI uses characters per word and words per sentence. Using multiple formulas gives a more reliable estimate than any single metric.
How many words do I need for accurate readability analysis?
Most readability formulas are calibrated for passages of at least 100 words. Short texts (under 50 words) can produce unreliable scores because a single long sentence or complex word disproportionately affects the result. For best accuracy, analyze complete paragraphs or full articles.