Calculate Text Complexity
Analyze readability with Flesch-Kincaid, Gunning Fog, and more. Visual gauges and detailed sentence analysis.
Readability Gauges
Grade Level
Master Your Content Clarity
Writing is only effective if it's understood. The Text Complexity Calculator is a professional-grade tool that scans your writing against industry-standard formulas. It instantly identifies the reading grade level, spotting complex words and overly long sentences that could confuse your audience.
Analysis Features
Multiple Formulas
Get a consensus score from Flesch-Kincaid, Gunning Fog, ARI, and Coleman-Liau indices simultaneously.
Visual Gauges
See at a glance if your text is "Easy", "Standard", or "Difficult" with color-coded meters.
Grade Level
Understand exactly who your audience is—from 5th graders to PhD researchers.
Text Stats
Deep dive into average sentence length, syllable counts, and complex word usage.
Document Support
Upload entire essays or reports to check consistency across long-form content.
Report Export
Download a comprehensive text file report of all your readability metrics for records.
Common Use Cases
- Content Marketing: Ensure blog posts are easy to read (Grade 6-8) for maximum engagement.
- SEO Optimization: Search engines favor clear, concise content that answers user queries simply.
- Academic Writing: Verify that your thesis meets the required complexity level for your field.
- Legal & Technical: Check manuals and contracts to ensure they aren't unnecessarily confusing.
Frequently Asked Questions
What is a good Flesch-Kincaid score?
For general web content and broad accessibility, aim for a Grade Level of 6-8. This corresponds to the reading ability of an average 11-13 year old. Academic or technical papers may range 12+.
What is the Gunning Fog Index?
The Gunning Fog Index estimates the years of formal education required to understand a text on the first reading. A score of 12 requires the reading level of a high school senior.
How is Reading Ease different from Grade Level?
Flesch Reading Ease is a 0-100 scale where higher numbers are better (easiest). Grade Level scores are the opposite; lower numbers are 'better' for simplicity (easier).
What counts as a 'Complex Word'?
In the Gunning Fog formula, a complex word is typically defined as any word with three or more syllables. Reducing these can significantly lower the required reading grade.
How can I improve my readability score?
To improve readability: shorten your sentences (break long ones into two), replace complex 3-syllable words with simpler synonyms, and use active voice instead of passive voice.
What is the Coleman-Liau Index?
Coleman-Liau relies on characters per word rather than syllables per word to estimate grade level. It is often used for automated analysis where syllable counting might be imprecise.
Can I upload a document?
Yes, you can upload text files (.txt, .md) directly to the tool to analyze entire articles, essays, or chapters at once.
Why is readability important for SEO?
Search engines prioritize content that gives a good user experience. Clear, easy-to-read content keeps users on the page longer and signals high quality to algorithms.
Is this tool free to use?
Yes, the Text Complexity Calculator is typically free to use without limits.
Does it support other languages?
Currently, the formulas (Flesch-Kincaid, etc.) are calibrated specifically for English sentence structures and syllable patterns. Results may be inaccurate for other languages.