Readability Score Analyzer

Paste any text and get a comprehensive readability analysis using six established readability formulas: Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog Index, Coleman-Liau Index, SMOG Index, and Automated Readability Index.

**Understanding readability scores**

Readability formulas estimate how difficult a piece of text is to understand. They analyze factors like sentence length, word length, and syllable count to produce a numeric score that corresponds to an approximate education level. While no single formula captures every aspect of readability (vocabulary familiarity, topic complexity, and cultural context also matter), using multiple formulas together gives a reliable picture of how accessible your text is.

**The six indices explained**

Flesch Reading Ease (0-100): Higher scores mean easier readability. Scores of 60-70 are "standard" and readable by most adults (8th-9th grade). Scores above 80 are "easy" and suitable for general audiences. Scores below 30 are "very difficult" and appropriate only for academic or technical readers. Developed by Rudolf Flesch in 1948, this is the most widely used readability metric.

Flesch-Kincaid Grade Level: Converts the Reading Ease score into a US school grade level. A score of 8.0 means an 8th grader could understand the text. Most general-audience writing targets grades 7-9. Technical documentation often falls in grades 10-12.

Gunning Fog Index: Estimates the years of formal education needed to understand the text on a first reading. Counts "complex words" (three or more syllables, excluding proper nouns and compound words). Scores of 7-8 are ideal for general audiences.

Coleman-Liau Index: Uses characters per word and words per sentence instead of syllable counts, making it faster to calculate. Generally produces results similar to Flesch-Kincaid.

SMOG Index (Simple Measure of Gobbledygook): Considered one of the most reliable formulas for healthcare and public information. Requires at least 30 words with 3+ sentences for meaningful results.

Automated Readability Index (ARI): Similar to other grade-level metrics but uses characters per word rather than syllables. Produces results comparable to Flesch-Kincaid and Coleman-Liau.

**When to use readability analysis**

Content writers check readability before publishing blog posts, articles, and landing pages. Technical writers ensure documentation is accessible to the target audience. Educators evaluate textbook passages and assignment sheets. Healthcare professionals verify that patient information materials are written at an appropriate level (ideally grade 6-8). Marketers optimize email copy and ad text for maximum comprehension. SEO professionals use readability as an indirect ranking signal — Google rewards content that provides a good user experience.

**Tips for improving readability**

Shorten sentences (aim for an average of 15-20 words). Use shorter words when possible. Break long paragraphs into shorter ones. Use active voice instead of passive voice. Replace jargon with plain language. Use transition words to guide readers between ideas.

**Privacy**

All analysis runs in your browser using standard formulas — nothing is transmitted anywhere.