Free online readability analyzer. Calculate Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog Index, Coleman-Liau, SMOG, ARI and more. Get instant text readability scores and reading level estimates.
This readability analyzer evaluates your text using six industry-standard readability formulas. It calculates the Flesch Reading Ease score, Flesch-Kincaid Grade Level, Gunning Fog Index, Coleman-Liau Index, SMOG Index, and Automated Readability Index (ARI). Each formula provides a different perspective on how easy or difficult your text is to read, helping you tailor your writing to your target audience. All calculations are performed client-side — your text never leaves your device.
The Flesch Reading Ease score rates text on a 0-100 scale. Higher scores mean the text is easier to read. A score of 60-70 is considered standard/plain English, easily understood by 13- to 15-year-old students.
The Flesch-Kincaid Grade Level translates the readability score into a U.S. school grade level. For example, a score of 8.0 means an eighth grader should be able to understand the text. Most popular novels are written at a 7th-grade level.
The Gunning Fog Index estimates the years of formal education needed to understand the text on first reading. It emphasizes sentence length and the number of complex words (words with 3+ syllables). A score of 12 corresponds to a high school senior reading level.
Readability formulas provide useful estimates but are not perfect. They primarily measure sentence length and word complexity (syllables), not semantic difficulty or topic complexity. Use them as guidelines, not absolute measures.
No. All calculations are performed entirely in your browser using JavaScript. Your text never leaves your device or is transmitted over the network.