Flesh is a cross-platform, open source Java application designed to quickly analyze a document and display the difficulty associated with comprehending it. It is available for all platforms that support Java. Flesh has been released under the GPL (license for use).
After processing a document, Flesh produces two scores: the Flesch-Kincaid Grade Level and the Flesch Reading Ease Score. Each of these scores is calculated after determining the number of sentences, words and syllables a document contains. Using those numbers, the Flesch-Kincaid Grade Level and Flesch Reading Ease Score can then be calculated.