The Gunning Fog Index, by Elizabeth Bezant, Writing to Inspire Blog
If you want to increase the readability of everything you write, consider using the Gunning Fog Index – more commonly known as the Fog Index. It is the copywriter’s favorite statistics measurement. The idea behind the Fog Index is to show you the education level your reader must hypothetically have to understand what the document says.
I am not asking you to “dumb it down.” But, remember that the goal in any legal writing project is to be understood, regardless of the complexity of the subject. If you are struggle with writing shorter sentence and paragraphs or simply making your writing more readable, this tool will help.
If you teach legal writing or any kind of writing course, encourage your students to use the Fog Index. It can be used by those who seek to improve their writing skills to a more sophisticated level. It can help anyone clarify their writing and write more concisely. But, most importantly, it gives you a way to determine whether what makes sense to you will make sense to anyone else.
Even though lawyers and judges have a high degree of education, when writing about complex issues, it helps to keep your document as simple and clear as possible. The goal is to keep your Fog Index from ten to fifteen. Major publications, such as the New York Times and Times Magazine, have a Fog Index of eleven to twelve. If your document is meant for a wide audience, go for a Fog Index of less than twelve. If you are writing a document that you want to be universally understood, your target is a Fog Index of less than eight. For example, the Bible’s Fog Index is six.
See also http://gunning-fog-index.com/.
For more readability tests, see http://juicystudio.com/services/readability.php. -CCE