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The Lexile Analyzer uses an algorithm to evaluate the reading demand — or text complexity — of books, articles and other materials. The Lexile Analyzer measures the complexity of the text by breaking down the entire piece and studying its characteristics, such as sentence length and word frequency, which represent the syntactic and semantic challenges that the text presents to a reader. The outcome is the text complexity, expressed as a Lexile measure, along with information on the word count, mean sentence length and mean log frequency.

Generally, longer sentences and words of lower frequency lead to higher Lexile measures; shorter sentences and words of higher frequency lead to lower Lexile measures. Texts such as lists, recipes, poetry and song lyrics are not analyzed because they lack conventional punctuation.

Determine the reading level of a piece of text

Use the Lexile Analyzer to measure texts in English or Spanish.

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