Automated Readability Index (ARI)

Measures text reading difficulty levels.

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About

The Automated Readability Index (ARI) is a tool that measures how hard text is to read. It gives a score that matches US grade levels - like 8th grade or 12th grade. Unlike other reading tests, ARI counts letters and characters instead of syllables, which makes it faster for computers to use. The formula looks at how many characters are in words and how many sentences there are. Higher scores mean the text is harder to read.

ScoreAgeGrade level
15-6Kindergarten
26-7First grade
37-8Second grade
48-9Third grade
59-10Fourth grade
610-11Fifth grade
711-12Sixth grade
812-13Seventh grade
913-14Eighth grade
1014-15Ninth grade
1115-16Tenth grade
1216-17Eleventh grade
1317-18Twelfth grade
1418-22College student

Indicators

Standards

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