About the Lexile® Text Analyzer API

The Lexile Text Analyzer is a utility for calculating the Lexile measure of a piece of professionally authored text. The Lexile Text Analyzer API exposes this functionality as a web service that can be accessed via the Internet using a convenient API. No hardware, software, installation or ongoing management is required. This service minimizes intrusive system integration by instead relying on service-oriented architecture.

The Lexile Text Analyzer measures text by breaking down the entire piece of text and studying its characteristics, such as sentence length and word frequency, which represent the syntactic and semantic challenges that a text presents to a reader. These characteristics are used to calculate the complexity of the text and produce a Lexile text measure.

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. For more information see Lexile® Framework for Reading.

For more information about Lexile measures and how measures should be reported, see Lexile® Reading Measures.