Lexile® Measures

Revision Assistant allows teachers to see the Lexile® text measures for each source that accompanies a Revision Assistant prompt. What are Lexile measures you ask?  

The Lexile Framework for Reading from MetaMetrics® is one of the most accurate and widely-used datasets for matching students with reading materials that will fit their skill levels and help them stretch those skills even further.  A Lexile measure represents both the complexity of a text, such as a book or article, and an individual’s reading ability.  A Lexile reader measure is a measure of a student's reading ability. A Lexile text measure is a measure of the text complexity for a book or piece of text. Continue reading to learn more about Lexile measures.


Where Can I Find Lexile Text Measures in Revision Assistant?

Revision Assistant allows teachers to see the Lexile text measures for each source that accompanies a prompt. Teachers will be able to see the following Lexile text measure information on each prompt page and each assignment page:

  • The range of Lexile text measures for a set of sources (in the right panel)  
  • The individual Lexile text measures for each source (under the title of each source)

Revision Assistant only shows Lexile text measures for prompt sources; not for the prompt writing instructions.  


How Are Lexile Measures Calculated?

A student gets his or her Lexile reader measure from a reading test or program. For example, if a student receives an 880L on her end-of-grade reading test, she is an 880 Lexile reader. Higher Lexile measures represent a higher level of reading ability. A Lexile reader measure can range from below 200L for emergent readers to above 1600L for advanced readers. Readers who score below 0L receive a BR for Beginning Reader. In some cases, for readers, a BR code is followed by a number and L (e.g., BR150L). A Lexile reader measure of BR150L indicates that the Lexile measure of the reader is 150 units below 0L. The smaller the number following the BR code, the more advanced the reader is. For example, a BR150L reader is more advanced than a BR200L reader.


A book, article or piece of text gets a Lexile text measure when it's analyzed by MetaMetrics. For example, the first "Harry Potter" book measures 880L, so it's called an 880 Lexile book. A Lexile text measure is based on the semantic and syntactic elements of a text. Many other factors affect the relationship between a reader and a book, including its content, the age and interests of the reader, and the design of the actual book. The Lexile text measure is a good starting point in the book-selection process, with these other factors then being considered. Lexile text measures are rounded to the nearest 10L. Unlike the reader measure, all text measures below 0L are currently reported as BR. MetaMetrics has conducted research to differentiate the BR text measures, and these measures will be available at a later date.


What is a Lexile Range?

The Lexile range is the span of Lexile text measures that a particular reader is forecast to comprehend while still encountering enough challenge to grow as a reader.   The Lexile text measure range for a reader is from 50L above her or his Lexile reader measure to 100L below it. The forecasted comprehension rate for the Lexile range is about 65% to 80%. When a reader reads within his or her Lexile range, this is referred to as a targeted reading experience. When a reader reads outside of his or her Lexile range, this is referred to as a mistargeted reading experience.


What Are Lexile Codes?

Sometimes a Lexile measure by itself is not enough information to choose a particular book for a particular reader. This is why some books get Lexile codes—two-letter designations that appear before the Lexile measure (for example, AD580L).

The Lexile code gives you more information about a book that relates to its developmental appropriateness, reading difficulty, and common or intended usage. Word frequency and sentence length—the two text characteristics that determine a Lexile measure—do not describe all of the content of a book. Lexile codes provide some context to the numerical measure to further help you guide readers toward fruitful reading experiences.  

The Lexile codes are listed below. Continue reading for an explanation of that Lexile code:

  • AD: Adult Directed
  • NC: Non-Conforming
  • HL: High-Low
  • IG: Illustrated Guide
  • GN: Graphic Novel
  • BR: Beginning Reader
  • NP: Non-Prose 



AD: Adult Directed

Picture books are frequently considered for an AD or "adult directed" code because they are usually read to a child, rather than a child reading them independently. This is the classic example of parent and child sitting together on the couch with the book open in their laps. Although seemingly easy reading, picture books can still present a challenging independent reading experience to an age-appropriate reader for reasons of text difficulty and book layout or design.

The text difficulty of picture books varies widely across the genre. For instance, Maurice Sendak's Where the Wild Things Are (HarperCollins Publishers) is a beloved read-aloud for preschoolers. Its Lexile measure of 740L, however, is around the average reading ability for someone ending fourth grade. Upon a closer look, the text comprises long sentences and contains some fairly high-level vocabulary such as "mischief," "private," "gnash," and "rumpus." The parent on the couch would help the preschooler sound these words out and decipher these long sentences. Therefore the book is coded adult directed and the measure is AD740L.

Additionally, picture books can have design elements that may visually complicate reading for a child. Factors such as font size, typeface, page layout, legibility, and the relationship between pictures and text may significantly impact reading comprehension. The story and illustrations in Where the Wild Things Are are perfect for young children. But the lines of the text are close together and the sentences are spread over multiple pages, often in long horizontal lines. These design elements may challenge a child's ability to read the book independently even if the text difficulty is well matched. Initially, a more advanced reader may need to read the book with a child.

NC: Non-Conforming

The NC code is applied to books that have a Lexile measure markedly higher than is typical for the publisher's intended audience or designated developmental level of the book. The Lexile measure of a book is compared to the Lexile range of readers in the intended audience in order to make an NC code determination.

The NC code is useful when matching high-ability readers with a book that's still at an appropriate developmental level. Alternatively, some picture books with disproportionately high Lexile measures may receive an AD (Adult Directed) code.

Seymour Simon's Amazing Aircraft (SeaStar Books) is coded NC710L. Its spine reads "grades 1-3" but its Lexile measure is higher than a typical early elementary school student's ability range. Therefore the book is coded as Non-Conforming.

HL: High-Low

A text designated as "HL" has a Lexile measure much lower than the average reading ability of the intended age range of its readers. Librarians and booksellers sometimes refer to young adult books with disproportionately low Lexile measures as "high-low" books, meaning "high-interest" plus "low-readability." These books receive an HL code. Often fiction, HL books are useful when matching older (grade 7 and beyond) struggling or reluctant readers with text at both an appropriate difficulty level and an appropriate developmental level.

Despite their short sentences and basic vocabulary, HL books are designed to appeal to readers at a more mature developmental level. For example, Beth Goobie's Sticks and Stones (Orca Soundings) is classified as a young adult book and measures 430L—an average reading ability for 2nd graders. The book's characters are high-school students who struggle with the many challenges that face high-school students such as dating and gossip. Therefore, the book is coded HL430L.

IG: Illustrated Guide

The IG code is applied to books that consist of independent pieces or sections of text such as in an encyclopedia or glossary. These text pieces could be moved around without affecting the overall linear flow of the book. Usually nonfiction, IG books are often used as a reference resource rather than read in their entirety like a storybook. Their distinguishing text characteristics include:

  • technical vocabulary, definitions, and pronunciation guides in parentheses

  • integration of illustrations and diagrams into the text

  • pull-quotes, factoids, and other categorical marginalia

  • the presentation of each discrete topic on one to two pages

These text characteristics do not necessarily impact reading comprehension or developmental appropriateness. Instead, the IG code conveys an idea of the kind of book and what the book typically will be used for in the classroom or library.

Birds of Prey by Dr. Gerald Legg (Franklin Watts Library) is coded IG. Separate paragraphs are arranged upon the page, functioning more like multiple-sentence captions. A particular reading order is neither indicated by the layout nor important to comprehension. Thus the book measure is IG320L.

GN: Graphic Novel

The GN code indicates that the book is a graphic novel or comic book. The text of GN books appears primarily in voice or thought bubbles integrated into comic book-style illustrations. Graphic novels tend to contain a larger percentage of dialogue than most other genres of books. They also typically lack some of the required text conventions of dialogue, such as putting "she said" after a quoted sentence, because illustration methods are used to indicate spoken text. The impact of picture support on reading comprehension is not captured in the Lexile measure of a graphic novel. 

To Dance: A Ballerina's Graphic Novel (Aladdin) , written by Siena Cherson Siegel and illustrated by Mark Siegel, is coded as GN610L.

BR: Beginning Reader

Beginning Reader (BR) is a code given to readers and text that are below 0L on the Lexile scale. In some cases, for readers, a BR code is followed by a number and L (e.g., BR150L). A Lexile reader measure of BR150L indicates that the Lexile measure of the reader is 150 units below 0L. The smaller the number following the BR code, the more advanced the reader is. For example, a BR150L reader is more advanced than a BR200L reader. Unlike the reader measure, all text measures below 0L are currently reported as BR. MetaMetrics has conducted research to differentiate the BR text measures, and these measures will be available at a later date.

Note that Beginning Reader (BR) is the only Lexile code that applies to both readers and text. All other codes apply only to text. Hop on Pop by Dr. Seuss (Random House) is a BR book.


NP: Non-Prose

The NP code is for any book comprising more than 50% non-standard or non-conforming prose. NP books do not receive a Lexile measure, merely the NP code. Some common examples of non-prose content are poems, plays, songs, recipes, and text with non-standard or absent punctuation.  Since the Lexile Framework is based on prose analysis, Maurice Sendak's Alligators All Around (HarperTrophy) is coded NP. The text of the book is not in complete sentences and lacks punctuation entirely. The text difficulty of such a book cannot currently be assigned a Lexile measure.



All the information on this page explaining what Lexile® Measures are, how to interpret them, how they are calculated, Lexile ranges and Lexile® codes was taken directly from MetaMetricsInc.com. The trademarks and names of other companies and products mentioned herein are the property of their respective owners. Copyright © 2017 MetaMetrics, Inc. All rights reserved.