ACCESSIBLE
Lower Grade Estimate
A lower SMOG result usually means the content is more accessible to a wider audience.
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SMOG Index Tool
Estimate readability grade level using the SMOG index.
Understanding Your SMOG Index Results
The SMOG Index estimates the education level needed to understand a text, with special attention to polysyllabic words.
REVIEW WORDS
Polysyllabic Words
Many long, multi-syllable words can increase complexity even when the topic is simple.
PLAIN LANGUAGE RISK
Too Advanced
A high SMOG score may make important information harder to understand for general users.
About This Tool
The SMOG Index Tool estimates the education level needed to understand a text passage, with emphasis on polysyllabic words. It is often used when clarity and accessibility are important.
Use it for public-facing content, health-style explainers, support resources, landing pages, and educational copy where misunderstanding can create friction.
Why It Matters
1
Review complex vocabulary
Identify where too many long words may slow comprehension.
2
Support clarity standards
Use a repeatable grade-level signal in content reviews.
3
Improve user confidence
Users trust content more when they can understand it quickly.
4
Make edits measurable
Compare before and after scores during copy simplification.
How To Improve
1
Paste a complete passage
Use enough text for a meaningful estimate.
2
Review long words
Check whether polysyllabic words are necessary or can be explained.
3
Simplify structure
Shorter sentences and cleaner paragraphs improve comprehension.
4
Balance clarity with accuracy
Keep essential terms, but define them in plain language.
Frequently Asked Questions
It is a readability formula that estimates grade level using the number of polysyllabic words in a text sample.
Yes. It can help identify complex copy that may be hard for users to process.
No. Keep necessary terms, but remove unnecessary complexity and explain important jargon.
Each formula measures different signals, so results can vary.
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