Automated Readability Index (ARI)
The Automated Readability Index (ARI) is an approximate representation of the U.S. grade level needed to comprehend the text.
ARI = (0.5 x ASL) + (4.71 x ALW) - 21.43
ASL = Average sentence length (the number of words divided by the number of sentences)
ALW = Average number of letters per word (the number of letters divided by the number of words)
The result is a number that corresponds to a numerical U.S. reading grade level.
Check out our free Online Text Analyser to analyse readability scores, and much more.