Flesch Kincaid Reading EaseBased on a 0-100 scale. A higher score means the text is easier to read. Low scores suggest the text is difficult to understand. 206.835 - 1.015 x (words/sentences) - 84.6 x (syllables/words) A value between 60 and 80 should be easy for a 12 to 15 year old to understand. Flesch-Kincaid Readability Test - Wikipedia, the free encyclopedia
Grade Level indicatorsThese equate the readability of the text to the US schools grade level system.
Flesch Kincaid Grade Level0.39 x (words/sentences) + 11.8 x (syllables/words) - 15.59 Flesch-Kincaid Readability Test - Wikipedia, the free encyclopedia
Spache Readability formaulaSimilar to the Dale-Chall Formula, as it used a list of familiar words, but used for third grade and below. Spache Readability Formula - Simple English Wikipedia, the free encyclopedia
Gunning Fog Score0.4 x ( (words/sentences) + 100 x (complexWords/words) )
SMOG Index1.0430 x sqrt( 30 x complexWords/sentences ) + 3.1291
Coleman Liau Index5.89 x (characters/words) - 0.3 x (sentences/words) - 15.8
Automated Readability Index (ARI)4.71 x (characters/words) + 0.5 x (words/sentences) - 21.43
Coleman Liau and ARI rely on counting characters, words and sentence. The other indices consider number of syllables and complex words (polysyllabics - with 3 or more syllables) too. Opinions vary on which type are the most accurate. In order to count the exact number of syllables a dictionary lookup is needed as there are no hard and fast rules to how many syllables there are in a word.