The Flesch–Kincaid readability tests are readability tests designed to indicate how difficult English texts are to understand. One of the tests is Flesch reading-ease, where the metric is Flesch reading-ease score (FRES).
Since not all texts are aimed at readers of all levels, you need to asses your audience’s level before testing. Scores can be interpreted as in the table below.
|100.00-90.00||5th grade||Very easy to read. Easily understood by an average 11-year-old student.|
|90.0–80.0||6th grade||Easy to read. Conversational English for consumers.|
|80.0–70.0||7th grade||Fairly easy to read.|
|70.0–60.0||8th & 9th grade||Plain English. Easily understood by 13- to 15-year-old students.|
|60.0–50.0||10th to 12th grade||Fairly difficult to read.|
|50.0–30.0||College||Difficult to read.|
|30.0–0.0||College Graduate||Very difficult to read. Best understood by university graduates.|