SMOG Readability Grade
Calculate the SMOG readability grade for any text. The Simple Measure of Gobbledygook for health and technical content.
About This Free Online SMOG Readability Grade
Our free online SMOG (Simple Measure of Gobbledygook) Grade calculator estimates the years of education needed to fully understand your text. SMOG was developed specifically for healthcare content and is recommended by the US National Institutes of Health for patient education materials. It counts polysyllabic words (3+ syllables) and uses a formula based on 30-sentence samples. SMOG is known for being slightly more conservative (predicting higher grade levels) than other formulas.
Features of Our SMOG Readability Grade
- Calculate SMOG readability grade instantly
- Polysyllabic word (3+ syllables) counting
- Healthcare-grade readability assessment
- Education years interpretation
- Real-time analysis as you type
- 100% private — browser-only processing
How to Use the SMOG Readability Grade
The SMOG Readability Grade works right in your browser — no signup, no installation. Follow these steps:
- Paste your text into the input area.
- View your SMOG grade level instantly.
- Review polysyllabic word statistics and percentage.
- Use the analysis to simplify health or technical content.
Frequently Asked Questions About SMOG Readability Grade
What is SMOG used for?
SMOG is specifically recommended by the US National Institutes of Health and other health organizations for evaluating patient education materials, consent forms, and health communication.
How is the SMOG grade calculated?
The formula is: 1.0430 × sqrt(polysyllabic words × 30 / sentences) + 3.1291. It uses a sample of 30 sentences near the beginning, middle, and end of the text.
Is SMOG more accurate than other formulas?
SMOG is more conservative (predicts 1-2 grades higher) than other formulas, which makes it preferred for health content where overestimating reading difficulty is safer than underestimating.
Why Choose the SMOG Readability Grade?
Text Toolbox provides free, private, and instant online tools. Unlike sites that require accounts or send your data to servers, the SMOG Readability Grade processes everything in your browser — your content never leaves your device. It is fast, lightweight, and works on any modern browser.