Reading Score
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Reading Note

What Is Gunning Fox Index?

For your essays, you should always consider how readable your text is. Robert Gunning, an American businessman, came up with a method for evaluating your text's readability in 1952.

The Gunning fox index is a metric used to measure the readability of a text. It uses the count of sentences, words, and complex words consisting of three or more syllables in the text. The less the index score is, the easier it will be for readers to understand what they are reading.

Here is the Gunning fog readability formula for a passage around 100 words.

0.4 × ((total words ÷ total sentences) + 100 × total complex words ÷ total words)

Here are the interpreted Fog index:

Fox IndexGrade
6Sixth grade
7Seventh grade
8Eighth grade
9High school freshman
10High school sophomore
11High school junior
12High school senior
13College freshman
14College sophomore
15College junior
16College senior
17College graduate

How Can You Decrease Gunning Fox Index?

You can decrease the score by using fewer words with three or more syllables. Words with three or more syllables make the passage harder to read.

What Is the Gunning Fox Index Calculator?

This online tool can be used to calculate the Gunning fog index of a text using the formula. All you have to do is to type or paste the whole content you want to evaluate into the input above.