Gunning Fog Index Calculator

How to use this text tool

1. Paste or upload your text.
2. Choose the analysis option or target value.
3. Run the tool and review the score, interpretation, and exportable report.

What this tool does

Calculate the Gunning Fog Index to evaluate long sentence load, complex word ratio, and professional readability. The result helps match writing difficulty, speed, or vocabulary level to the intended audience.

Scores are guidance estimates, not editorial judgment. Review context, audience, and purpose before changing final copy.

Example

Paste a blog introduction, speech script, classroom handout, business email, or article draft to generate an instant writing analysis report.

Use cases

• SEO content editing
• Presentation and script preparation
• Business and academic writing review
• Education material readability checks

Tips for better output

• Shorten very long sentences.
• Use simpler alternatives for unnecessary complex words.
• Keep paragraphs focused and skimmable.
• Match vocabulary to the reader, not the writer.

Processing details

Processing runs locally in the browser. Syllables and complex words are estimated with rule-based logic, so unusual names or technical terms may require manual judgment.

For non-English text, readability formulas may not reflect true difficulty because these indexes were designed mainly for English.