What Is Gunning Fox Index?
The Gunning Fog Index is a metric used to measure the readability of a text, developed by Robert Gunning, an American businessman, in 1952.
It considers the number of sentences, number of words, and the number of complex words consisting of three or more syllables in the text. The lower the index score, the easier it is 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 Index | Grade |
|---|---|
| 6 | Sixth grade |
| 7 | Seventh grade |
| 8 | Eighth grade |
| 9 | High school freshman |
| 10 | High school sophomore |
| 11 | High school junior |
| 12 | High school senior |
| 13 | College freshman |
| 14 | College sophomore |
| 15 | College junior |
| 16 | College senior |
| 17 | College 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.