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Lexile Text Analyzer
Learn how to prepare text and use your analyzer to get Lexile text measures.
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.
Text Analyzer API
Use a single call to submit text for analysis
Measure Text

Products, Tools, and Services
- Score Interpreter
  Retrieve student Lexile and Quantile measures and forecast performance on an upcoming assessment.
- Get Measurements
  Use our products, tools, services and APIs to get the measurements you need.
- Lexile Text Analyzer
  Learn how to prepare text and use your analyzer to get Lexile text measures.
  - 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.
    - Before You Begin
    - Text Preparation Guidelines
    - Lexile Text Analyzer Editor Assistant
      How to use the Editor Assistant
    - Lexile Text Analyzer Professional
      How to use Lexile Analyzer Professional
    - Lexile Text Analyzer Spanish
      How to use Lexile Analyzer Spanish
    - Text Analyzer API
      Use a single call to submit text for analysis
      - Measure Text
  - Lexile Text Analyzer FAQ
    The Lexile Text Analyzer® is designed to evaluate the reading demand or complexity of a text.
- WordBank
  Discover words across grade levels and subject areas that students will encounter in classroom reading.
- The Hub
  An online platform that provides easy access to more than a dozen reading and math tools.
- Quantile Sequencing Service
  Get research-driven information to direct users to appropriate resources for learning a skill or concept.

Measure Text

Overview

You can use this method to send text and receive a Lexile measure. Before you submit text for analysis you should make sure it's properly formatted.

Method

analyzer.analyze(text, [language])

Parameters

The only parameter you need to include is the text to be analyzed.


Parameter	Type	Description
`text`	String	The text to be analyzed.
`language`	Optional String	The language of the text. This is optional and does not need to be provided.

Response

The response will look similar to

{
    'lexile': 400,
    'lexile_display': '400L',
    'mlf': 3.7460290817322215,
    'msl': 4.5,
    'version': '6.0.0',
    'word_count': 9,
}


Parameter	Type	Description
`lexileMeasure`	Number	The Lexile measurement. Example: 400
`lexileMeasureDisplay`	Number	This is the measure you should use when you publish or share a measurement. The letters included with the measure indicate what type of measure this is. In this example, the L means this is a Lexile measure. Example: 400L
`mlf`	Integer	Mean Log Word Frequency The logarithm of the number of times a word appears in each 5 million words of the Lexile Corpus of 1.5 billion words. Word frequency is not the number of times a word appears in a specific passage, but the frequency of the word in the Lexile Corpus.
`word_count`	Number	Total number of words in a text.