Fry’s Readability Formula
There are lots of readability formulas out there to help designers create prose with a specific level of readability. Flesch Formula, Dale-Chall formula, Farr-Jenkins-Palerson formula, Kincaid Formula, Gunning Fog Index and Unsear Write Index.
I recently used Fry’s Readability Formula in my website assignment to make sure that the writing style is at the approximate reading level of the targeted audience. In this case University reading level. However, I fell into the trap of writing for the formula and not as a as a guide to verify after I have written. E.g., I wrote more sentences per paragraph which may be more appropriate for lower level readers, but may hinder readability for advanced readers who are my targeted audience. So I had to balance simple language without being overly simple to avoid obscuring meaning.