About the Lexile Text Analyzer The Lexile Text Analyzer® is designed to evaluate the reading demand or complexity of a text. This process is referred to as measuring, and the result is a text measure that represents the difficulty of analyzed text. The Lexile Text Analyzer measures text by evaluating the entire piece and its characteristics, such as sentence length and word frequency, which represent the syntactic and semantic challenges that a text presents to a reader. The outcome is the reading difficulty, expressed as a Lexile measure, along with the Word Count, Mean Sentence Length, Mean Log Frequency, and Early Reading Indicators for texts 650L and below.