CLEAR
Low Fog Score
A lower score usually means the text is easier to understand without rereading.
Free to use • No registration required
Gunning Fog Index Tool
Estimate how many years of education may be needed to understand a text passage.
Understanding Your Gunning Fog Index Results
The Gunning Fog Index estimates how many years of education a reader may need to understand the text on first reading.
REVIEW
Complex Word Load
Complex words and long sentences can raise the score and make business copy feel heavy.
FRICTION
High Reading Effort
A high score can reduce comprehension in onboarding, sales pages, docs, and email campaigns.
About This Tool
The Gunning Fog Index Tool estimates text complexity using sentence length and complex word usage. It is useful for identifying copy that may feel dense, formal, or slow to read.
Use it for blogs, reports, policy pages, emails, onboarding text, and landing pages where heavy copy can reduce engagement.
Why It Matters
1
Find dense writing
Spot long sentences and complex terms that make reading slower.
2
Improve business communication
Make reports, emails, and web pages easier for more people to understand.
3
Support content optimization
Use the score to prioritize edits before publishing.
4
Reduce cognitive load
Clearer text helps users make decisions faster.
How To Improve
1
Analyze the full text
Paste a representative section for a more useful score.
2
Review long sentences
Split sentences that contain too many ideas.
3
Reduce complex words
Use simpler alternatives where they keep the same meaning.
4
Edit for flow
Improve headings, paragraph breaks, and transitions, then re-test.
Frequently Asked Questions
It estimates reading difficulty based on sentence length and complex word frequency.
Not always, but it may indicate the content is harder for a general audience.
Yes, but judge results against the intended audience and necessary terminology.
Use shorter sentences, clearer wording, and fewer unnecessary complex words.
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PRO FEATURE
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