Readability Analyzer
Compare five verified readability formulas and see whether your writing hits the mark for your audience — marketing, healthcare, legal, investor, or technical readers. Sharpen your copy so it stays engaging and accessible.
Audience-focused guides
Learn how to write for investors, patients, plain-language compliance, and more.
Writing for Investors
Check whether your pitch, update, or memo hits the right executive register.
Plain Language Compliance
Meet legal and government readability expectations with the right formula.
Writing for Patients
Why health literacy guidance uses SMOG and how to keep patient-facing text clear.
Formulas Explained
What each readability score measures and why the numbers can differ.
Frequently asked questions
What is a good readability score?
It depends on your audience. For general public and marketing content, aim for a Flesch-Kincaid grade of 6–8. For patient-facing healthcare materials, a SMOG grade below 8 is recommended. Investor and executive writing typically works best at grade 9–11. There is no single “good” score — the right target depends on who you are writing for.
Why do different readability formulas give different scores?
Each formula measures different aspects of text complexity. Flesch-Kincaid and Gunning Fog use syllable counts and sentence length, Coleman-Liau uses letter counts instead of syllables, and SMOG focuses specifically on words with three or more syllables. Because they measure different things, they often disagree by a grade level or more on the same text. This is normal and expected, not a sign the tool is broken.
What readability level should I aim for?
For a broad consumer audience, grade 6–8 is the most common target. Patient and healthcare materials should aim for a SMOG grade of 6 or below. Legal and government plain-language standards typically use a grade 6–8 ceiling. Investor-facing writing works best at grade 9–11. Technical or clinical peer-to-peer writing has no fixed target — vocabulary complexity is expected, but unnecessarily long sentences should still be avoided.
Is my text sent to a server?
No. All readability analysis runs entirely in your browser using JavaScript. The text you paste is never transmitted to a remote server. Your content stays on your device.
Why does this tool use SMOG instead of Flesch-Kincaid for healthcare writing?
SMOG is calibrated for full comprehension rather than general ease of reading, which is why it is the preferred formula in health literacy guidelines. It tends to score 1–2 grade levels higher than Flesch-Kincaid for the same text, so a document that passes Flesch-Kincaid may still fail a SMOG-based compliance check. For patient-facing materials, SMOG gives the more conservative and therefore safer estimate.
How accurate is the syllable counting?
Automated syllable counting uses a heuristic algorithm that works well for standard English but may have minor inaccuracies on unusual words, proper nouns, or borrowed terms. This is an inherent limitation of syllable-based readability formulas across all tools, not just this one. The results are consistent enough for comparative analysis and audience targeting.
Can I use this tool for professional compliance checking?
This tool is useful as a readability guide for professional writing, but it is not a substitute for formal legal, medical, or regulatory review. Use the scores to identify potential readability issues and improve clarity, then verify against any specific compliance standards required for your use case.