While BISAC codes may not mean much to the average reader, they do play an important role in helping those readers discover your book. The right BISAC codes can help retailers and booksellers understand where your book belongs, position it among similar titles, and help interested readers find it.

BISAC codes are only one part of your book’s metadata, however. Your subject categories, keywords, and other details work together to describe your book and help it reach its intended audience.

In this guide, we’ll break down what BISAC codes are, how they impact your book’s discoverability, and how to make sure your metadata accurately represents your book and reaches your intended readers.

Quick Overview of BISAC Codes and Subject Matter

A BISAC code is a nine-character alphanumeric identifier that publishers, librarians, and booksellers use to categorize and organize books by subject. The codes are developed and managed by the Book Industry Study Group (BISG).

Having the right BISAC codes attached to your book is important for placing your book in the right category on a retailer’s shelves or website. Because BISAC codes describe a book’s subject matter, they give librarians and booksellers a standardized way to understand what a book is about and, in some cases, who the intended audience may be.

Some books covering multiple subjects have more than one BISAC code. However, BISG best practices suggest using no more than three codes per book. Many books can be accurately represented with a single, highly specific subject code.

BISAC codes are updated annually. The BISG reviews the existing codes each fall, updating existing subjects and adding new ones as needed. Authors should periodically review current BISAC guidelines and their book’s metadata to ensure that their book is still correctly categorized for new readers and booksellers.

Start Here: Use the BISAC Subject Heading List on the BISG Website

BISAC codes are not automatically assigned to a book. Instead, the author or publisher selects the subjects that best represent the book. There is no fee to use BISAC codes, and no special permissions are required. The current BISAC subject heading list is available through the BISG website.

To find the right BISAC codes for your book, start by reviewing the BISAC subject heading list. Subjects are organized by broad categories and then divided into increasingly specific topics. This structure allows you to move from a general subject to a more precise description of your book.

The more specific and accurate your BISAC codes are, the more clearly they communicate your book’s subject to potential readers and booksellers. For example, a book about nature could potentially fall into a broad “nature” category, while a book about desert ecosystems could use the BISAC code NAT045010 (Nature / Ecosystems & Habitats / Deserts). The book is still about nature, but that more specific code distinguishes it from books about fossils, caves, or wildlife. 

As you review the list, look for the subject headings that most closely match your book. Pay attention to new BISAC codes, which may be marked with an asterisk or other indicator. New codes may not yet be fully integrated into the wider publishing network, so authors may want to pair a newer, highly specific code with a more established subject when appropriate.

Identify Your Book’s Core Subject Matter and Target Audience

Before looking through BISAC codes, take some time to identify exactly what your book is about. 

Make a list of your book’s primary topics, themes, genres, and subjects. Then consider who is most likely to read the book and what those readers are looking for.

Setting, genre, content, and intended audience all matter in choosing a BISAC code. For example, a mystery novel set in a restaurant kitchen could potentially be categorized in different ways depending on its focus and writing style. A matter-of-fact police procedural (FIC022020) will fall under a different subject than a cozy culinary mystery (FIC022130) or a fun detective story written for juvenile audiences (JUV028000).

Once you’veidentified your book’s major themes and audience, you can compare those characteristics with the BISAC subject heading list. This gives you a starting point to identify the codes that best describe your book.

Two-Step Selection Process for Subject Codes

To choose your subject codes, start with the highest-level category that applies to your book, such as Fiction or Travel. Keep in mind that fiction is divided into categories by audience age level, including general fiction, juvenile fiction, and young adult fiction. 

After you select a category, look through the specific subject codes available within it. Most BISAC codes feature multiple levels of specificity, allowing you to easily move from a broad subject to a more precise one.

Create a short list of three to five potential subject codes. Rank your list by how well each option represents your book and your target audience.

BISG recommends having no more than three codes per book. In many cases, one well-chosen code is enough.

Drill Deeper: Choose the Most Specific BISAC Codes

When selecting BISAC codes for your book, it’s important to be as specific as possible. If a general category and a more precise subject both apply to your book, the specific category will usually provide a clearer description of the book’s subject.

Specificity can also help you reach niche audiences. A reader searching for a particular subject is more likely to benefit from a specific subject code than a general category that encompasses many unrelated books.

Fiction books should always begin with the BISAC fiction categories, while nonfiction books should use the relevant nonfiction subject categories. While books can have more than one BISAC code, do not mix fiction and non-fiction codes for the same book. Keeping the codes consistent with the book’s format and content helps prevent confusion about where the book belongs.

Picking the Primary BISAC Code and Ordering Subject Codes

If your book has more than one BISAC code, you’ll need to designate one as the primary subject code. 

Your primary BISAC code should be the one that most represents your book’s central subject or genre and is most relevant to your intended audience. This is particularly important as some retailers use only the first BISAC code to determine a book’s placement.

Any remaining codes should be ordered by secondary importance. The goal is to give retailers, booksellers, and readers a clear picture of what your book is about rather than attempting to capture every possible topic mentioned in its pages.

When to Use Non-Classifiable or General Subjects

While most books can be assigned to a specific BISAC subject code, there are some instances in which a title may require a non-classifiable or general subject code. 

Blank books, for example, may use the code NON000000: NON-CLASSIFIABLE.

For books that contain substantive content, however, a specific subject should generally be used when available. A non-fiction book about all kinds of pets, for example, may be classified as PET000000 (PETS / General) if none of the specific subcategories, such as dogs, cats, horses, or amphibians, accurately capture the broad scope of the book.

The key is accuracy. Don’t use a general code just because a specific subject requires more research.

Keywords, Amazon Categories, and Metadata Interaction

BISAC codes and keywords both help with the discoverability of your book, but they serve different purposes.

While BISAC codes help retailers and librarians understand where to place your book, keywords help to ensure that readers can find it through online searches. Your BISAC subjects do not necessarily need to appear verbatim in your keyword list, although they can be useful keyword terms. 

For example, an appropriate BISAC code for a young adult fantasy novel might be YAF019020 (YOUNG ADULT FICTION / Fantasy / Dark Fantasy). “Dark fantasy” could also be an important keyword to include in your book’s metadata, as it describes the type of story a reader might actively search for.

The most important thing is that your metadata is cohesive, with each element working as a separate signal pointing to the same place. When your keywords and BISAC subjects accurately reflect the same book, they reinforce the overall presentation and placement of your title. 

When preparing a book listing for Amazon and other online retailers, enter the primary BISAC code first in the appropriate metadata fields, followed by secondary subject codes and any relevant keywords as required by the platform.

New Codes and Requesting Changes Via the BISG Website

BISG reviews current and requested codes each fall, issuing an updated list of BISAC codes for ongoing use.

If your book covers a subject that does not appear in the current BISAC list, you can review BISG’s process for requesting a new subject. BISG does not typically create a new code for a single title. It is more likely to add a code when there is enough evidence to represent a broader need. 

If you request a new code, it’s helpful to provide broad examples that clearly demonstrate the need across multiple books or publishing contexts. Because the codes are updated annually, it’s also helpful to check the BISG periodically for updates rather than relying indefinitely on an older list.

Consistency Across Formats and Distribution

Because BISAC codes reflect the subject matter of your book rather than a specific format or edition, it’s important to use consistent subject codes across all retailers, formats, and editions. 

Before publishing, verify that the BISAC information in your distributor and retailer listings matches the metadata you selected. If you decide to change your subject codes later, make sure you update all listings, including distributor records.

Consistent metadata makes it easier for retailers and distributors to accurately represent your book across different formats.

Monitor Performance and Test Adjustments

BISAC codes are an important part of a book’s discoverability, but they’re not necessarily permanent.

As you monitor your book’s sales and discoverability, you may find that one subject description more accurately reflects how readers are finding and engaging with your book than another. New BISAC codes may also provide a more specific way to describe your book and connect with its target audience. Reviewing your metadata periodically can help you identify opportunities for improvement. 

Authors should review their sales and discoverability data on a regular basis, such as quarterly. If a book appears to be underperforming in its current subject area, consider whether an alternate BISAC code better represents its contents and audience.

You’ll want to make changes carefully, however. Metadata should change only when necessary, not in response to short-term fluctuations. If you test a different subject code, give the change enough time to produce meaningful information before you make any other adjustments. 

Common Mistakes to Avoid with Subject Codes

Some of the most common mistakes authors make with subject codes include:

• Choosing a general category when a more appropriate specific category exists.
• Mixing adult and juvenile age brackets, which confuses the intended audience.
• Including conflicting fiction and nonfiction codes on the same book. 
• Choosing subject codes based on a minor element of the book rather than its primary subject or genre.
• Overloading keywords with repeated BISAC labels instead of using related terms.
• Using different BISAC information across distributors and retailer listings.

The key is to keep your BISAC codes simple, accurate, and consistent. Your metadata does not need to describe every detail of your book. It simply needs to give readers and the publishing ecosystem an accurate picture of what the book is and who it’s for.

Practical Examples and Mini Case Studies

The best way to understand BISAC codes is to see how they work in practice. Consider these examples:

Example 1: A Biography

Imagine you have written a biography of a well-known American jazz musician. The book covers the musician’s childhood, career, recordings, major performances, and influence on American music.

For a book focused primarily on the musician’s life and career, BIO004000 (Biography & Autobiography / Music) could be an appropriate primary BISAC code. BISG also provides other biography subjects, such as BIO005000 (Biography & Autobiography / Entertainment & Performing Arts) that may be appropriate depending on the person and the focus of the book.

The important consideration is the book’s primary focus. If the book is fundamentally a biography of the musician, a biography subject should take priority over a general music category. If the book instead examines the development of jazz as a genre and uses the musician primarily as a case study, a music subject may be more appropriate.

The BISAC code should describe what the book fundamentally is, not simply one topic that appears in it.

Example 2: A Mystery Novel

Now imagine a mystery novel about a pastry chef who discovers a body in the kitchen of a small-town bakery.

The book’s setting includes food and cooking, but its primary genre is mystery. If the novel has the characteristics of a cozy culinary mystery, FIC022130 (Fiction / Mystery & Detective / Cozy / Culinary) could be an appropriate subject code. If the story is instead a more traditional mystery, police procedural, or another type of mystery, a different code within the Mystery & Detective category may be more accurate.

The protagonist being a pastry chef does not automatically make the book a cooking title. Its primary BISAC code should reflect the book’s actual genre and subject, while details such as the bakery setting or culinary themes can be reinforced through keywords and other metadata.

This is a good example of why choosing a BISAC code requires looking at the whole book rather than simply choosing the most frequent subject.

Example 3: How Keywords Can Change Discoverability

Consider a young adult novel about a teenager who discovers that the abandoned amusement park in her town is haunted.

The book’s BISAC subject might identify it as young adult supernatural fiction using code YAF045000 (Young Adult Fiction / Paranormal, Occult & Supernatural). While this code accurately groups the title with other YA paranormal books, it doesn’t give any more insight into its contents.

Keywords can capture a book’s more distinctive elements, helping to distinguish it from others in the same category. They also give readers additional ways to find your book through online searches. “Haunted amusement park,” “teen ghost story,” or “abandoned amusement park” give your book a better chance of appearing when readers search for those specific topics.

The goal isn’t to fill the metadata with every possible search term, but to provide additional language that connects the book with the ways its intended readers might describe or search for it.

Metadata Entry Checklist Before Publishing

When you’re ready to publish your book, make BISAC codes part of your publishing checklist. Take the time not only to choose the metadata that best represents your title, but also to review it before publication. You’ll want to catch any errors and inconsistencies before your book reaches retailers and distributors.

Before submitting your metadata, make sure that:

• Your primary subject code is listed first in where required.
• Secondary codes are listed in order of importance.
• Your subject codes accurately reflect your book’s subject or genre.
• You’ve chosen the most specific subject codes available rather than a general category.
• Your codes are correctly classified as fiction or nonfiction.
• Your codes reflect the intended audience by age.
• Your keywords complement your BISAC subjects rather than repeating them.
• All metadata is consistent across retailers, platforms, and formats.

After publication, take a moment to check your book’s retailer listings as well. Confirm that the information appears as expected and that the categories assigned by individual retailers accurately reflect your chosen metadata.

It’s also important to also note that metadata isn’t something to set and forget about. As your book moves through the publishing process, check your listings regularly to help prevent small metadata issues from becoming bigger discoverability problems.

Final Resources and Next Steps

Choosing BISAC codes doesn’t have to be complicated. Start with the official BISAC heading list published by the Book Industry Study Group (BISG) and use it to identify the subjects that most accurately describe your book.

Once you’ve selected your codes, keep a record of them along with your other publishing metadata. Documenting your primary and secondary BISAC subjects can make future updates much easier, especially if you publish your book in multiple formats and editions. It can also help you compare your original data with the updated subject codes released by BISG each year.

It’s also worth making metadata review part of your regular publishing routine. Schedule an annual check-in to review the current BISAC subject list, confirm that your selected codes and keywords still accurately describe your book, and make sure your metadata remains consistent across your distribution channels.

Your BISAC codes and keywords may not be something readers notice when they pick up your book, but they are an important part of the information that helps the publishing industry understand where your book belongs. Taking the time to choose them thoughtfully can help connect your book with readers looking for it.