The Lexile codes are:

• AD - Adult Directed: Better when read aloud to a student.
• HL - High-Low:  High-interest and age-appropriate content at a lower reading level.
• IG - Illustrated Guide: Nonfiction materials often used for reference.
• NC - Non-Conforming: For high-ability students who still need age-appropriate content.
• BR - Beginning Reader: For students with a Lexile measure below 0L. BR is the only Lexile code that applies to both readers and text. 
• GN - Graphic Novel: Graphic novels or comic books.
• NP - Non-Prose: Text with non-standard or absent punctuation (e.g. poetry or plays).

Want to dig a little deeper into Lexile codes, what they mean, and how you can use them with your students? Here you go:

AD: Adult Directed

Picture books are often labeled AD, or “adult directed,” because they are usually read to a child, rather than independently. Although these books may seem like easy readers, some picture books can still present a challenging independent reading experience to an age-appropriate reader for reasons of text difficulty, layout, or design.

Take the example of Maurice Sendak’s Where the Wild Things Are (HarperCollins Publishers), a read-aloud book for preschoolers. It has a Lexile text measure of 740L, which is around the average reading ability for a child completing fourth grade, and is coded AD. When you look closely at the text, you can see why it gets a “higher” Lexile text measure than the intended audience. The sentences are long and contain fairly high-level vocabulary, such as “mischief,” “private,” “gnash,” and “rumpus.” A parent or educator could help the preschooler sound these words out and decipher the long sentences. 

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 may be appropriate for young children, but the lines of 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

Sometimes, high-ability readers have trouble finding books that challenge their reading skills but still have age-appropriate content. The NC code helps identify these books, which have received a higher Lexile text measure but are appropriate for a younger audience.

For example, Seymour Simon’s Amazing Aircraft (SeaStar Books) is coded NC900L. Its spine reads “grades 1-3” but its Lexile text measure is higher than a typical early elementary school student’s ability range. This book might be hard to read for most students in grades 1-3 but engaging and challenging for students with above-average reading abilities.

HL: High-Low

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

For example, Beth Goobie’s Sticks and Stones (Orca Soundings) is classified as a young adult book and measures 430L — the average Lexile reader measure for second graders. The book’s characters are high school students who struggle with the many challenges that face teenagers, such as dating and gossip.

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 can be moved around without affecting the overall linear flow of the book. 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 or contrasting type
• integration of illustrations and diagrams into the text
• pull-quotes, factoids, and other categorical marginalia
• 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 it typically will be used for in the classroom or library.

Birds of Prey, by Dr. Gerald Legg. (Franklin Watts Library) has a Lexile measure of 980L and 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.

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. They also typically lack some of the required text conventions of dialogue, such as putting “she said” after a quoted sentence, because illustrations 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 lower the number following the BR code, the more advanced the reader or text is. The higher the number, the less complex the text is or the less skilled the reader. Beginning Reader (BR) is the only Lexile code that applies to both readers and text. Good Night, Gorilla, by Peggy Rathmann, (Random House) is a BR book with a Lexile measure of BR50L.

NP: Non-Prose

Some books don’t receive Lexile text codes because they aren’t “prose.” These books might feature poems, plays, songs, recipes, and text with non-standard or absent punctuation. The NP code is for any book comprising more than 50 percent non-standard or non-conforming prose. NP books do not receive a Lexile measure, merely the NP code.

An example of a book coded NP is Maurice Sendak’s Alligators All Around (HarperTrophy). 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.