Just like human beings, all books have a distinctive genetic fingerprint: the ISBN. In order for your masterpiece to be sold in brick and mortar stores, distributed in libraries, or nominated for awards, it’s going to need one of these unique codes.

But what is an ISBN, exactly? How does it work, why is it important, and how can you get one? Let’s take a closer look at what you need to do to get your own ISBN for your book!

What is an ISBN?

An ISBN is a thirteen-digit number that uniquely identifies a published book. ISBNs help publishers and booksellers communicate with each other, because a book’s ISBN is the same everywhere in the world. Writers receive ISBNs from their publishers, or they can purchase them from an ISBN agency. “ISBN” stands for “International Standard Book Number.”

(You’ll sometimes see it being called an ISBN number, a victim of the RAS syndrome, or “redundant acronym syndrome syndrome.”)

Each different edition of a book gets its own unique ISBN to identify it. For instance, if you release the same book title as a paperback, a hardcover edition, an e-book, and a Super Deluxe Special Edition With Fancy Endpapers, each of those versions will get their own separate ISBN.

Some ISBNs are ten digits; we’ll look at why below.

These numbers are issued to both publishers and authors by agencies that specialize in managing ISBNs. We’ll take a closer look at how to get a new isbn number a bit later on in this article.

“ISBN” stands for “International Standard Book Number.”

Where did ISBNs come from?

WHSmith, a major bookstore chain, launched the first ISBN system in the UK in 1967 as the “Standard Book Numbering System.” These were originally nine digits, although they switched to ten digits shortly after. By the early 1970s, ISBNs had become accepted worldwide.

In 2007, the International ISBN Agency officially switched from ten-digit numbers to thirteen digits. That means that anything published before 1967 won’t have an ISBN number, anything published between 1967 and 2007 will have a ten-digit ISBN number, and anything published after 2007 will have a thirteen-digit ISBN number.

Note that these dates apply to physical books, not stories. For example, a book by James Joyce wouldn’t have originally have had an ISBN number because it was written before the ’60s; however, a re-released copy of the same book printed after 1967 would have an ISBN assigned to it.

What do all those numbers mean?

ISBN numbers may look random, but they’re mathematically calculated using a special formula. A modern ISBN consists of five distinct parts (older, ten-digit ISBNs are made up of four parts). Each of these parts communicates something specific about the book.

Diagram of an ISBN number

As an author, you don’t need to be too concerned with knowing what all of these numbers are for—there won’t be an exam. But understanding the way it’s put together can make things a little easier if you’re looking at getting your own ISBN for your book.

Prefix element

The prefix element is always three digits—978 or 979 (this may change in future as these numbers get used up). Ten-digit ISBN numbers don’t have this piece. It just tells us that we’re looking at an ISBN number instead of another type of product code.

Registration group element

This number tells us what language the book is in. Majority languages are usually only one digit, but less widely spoken languages can be several. English-language books are 0 or 1, French-language books are 2, German is 3, and so forth.

Registrant element

This step represents the particular publisher. If you’re a self-published author, you’ll get your own registrant element, or publisher code. Traditional publishers with a registered publishing company will have the same registrant element for all their books.

Publication element

This is the crux of the book’s ISBN number. Every unique title and edition gets a different publication element to identify which volume it is. This is how retailers and readers can tell one edition or format of your book from another.

Check digit

This final number of a book’s ISBN will always be a single digit, and it shows that your unique number has been verified by the correct authorities.

Why is an ISBN important?

The ISBN is used to help identify your book. When publishers, retailers, and libraries order and sell books—whether it’s a print version or a digital book—they rely on the ISBNs to keep track of sales and their own stock. It also gives your book a place in library catalogues.

If you don’t get an ISBN number, it will be impossible for a customer to know if they’re getting one edition of the same book over another (or even the right title).

Getting an ISBN is an essential step in your book-publishing journey.

You won’t necessarily need to get an ISBN number for self-published books, especially if you’re only planning to sell it through your personal website or direct at events. But if you self-publish without an ISBN number, it’ll limit who you’ll be able to reach with it.

For example, you may only be able to distribute on your own or through a specific online publishing platform. With an ISBN, you can distribute through any retailer or platform all around the world.


So now we have a clear idea of what an ISBN is and why it’s important. But there are a couple other book identification numbers you might come across in your literary travels: ISSNs and ASINs.

ISSN stands for “International Standard Serial Number.” These are eight digits, shorter than an ISBN, and are used for recurring publications. This might be a magazine or literary journal, or a novel that’s released in chapbook-like episodes (like a limited series on Netflix).

ASIN stands for “Amazon Standard Serial Number.” These apply to all products sold through Amazon, not just books. ASINs are ten digits, like oldschool ISBNs, and are assigned by Amazon’s self-publishing platform. In fact, they don’t cost anything extra in addition to your self-publishing costs.

Sounds pretty great, right? Tread carefully, my friend—Amazon’s free asin number only allows you to seek through Amazon. Although you’ll sometimes see this being called a “free ISBN,” this number isn’t recognised by the publishing industry and won’t let you distribute through libraries or brick and mortar stores.

The difference between ISBN and barcode

You’ll notice that most books have both an ISBN number and a barcode (sometimes written as bar code). The barcode might even have the ISBN right on it, but they’re not the same thing or interchangeable.

You can think of it this way: an ISBN has to do with what a book is and where it comes from. A barcode has to do with money. It communicates how much the book costs and what currency the book’s fixed price is in.

Your book’s ISBN will be the same everywhere, but it might be sold under different barcodes.

You’ll often see a second number on the barcode alongside your ISBN—the UPC (in North America—this stands for Universal Product Code) or the EAN (in Europe—this stands for European Article Number). The shop uses these codes to tell them the set price. As an author, you just need to know your ISBN number.

Who can get an ISBN number?

ISBN numbers are available to anyone who’s written a book. If you’re a traditionally published author, your publishing house will supply you with one. If you self-publish your book (including ebooks), it’s possible for you to get an ISBN number in the same way that traditional publishers do. Alternatively, you may be able to get a free ISBN from your self-publishing platform.

If you’re only distributing through your personal website, then it’s up to you whether or not to get an ISBN number. You may not want to incur the extra cost right away, but having one up front ensures that more retailers and libraries will be able to buy your book and readers will have an easier time finding it.

How to get an ISBN number as a self-published author

Getting your own ISBN numbers will help you sell more books in more places. It also makes it easier for your fans to find your book and buy it.

Fortunately, getting your own ISBN as a self-published author is very easy! There’s no universal, international ISBN agency that handles all books (yet), so the processes can be a little different depending on where you’re located.

We’ll walk you through hot to get an ISBN number when you self-publish and other info you need to know.

If you’re publishing a book in multiple formats, you’ll need multiple ISBNs.

Getting an ISBN number in the United States

Bowker is the official ISBN agency in the United States. Visit their main site to start the process of purchasing an ISBN for your book. They’ll present you with a number of different pricing options.

You’ll want to know how many ISBNs you want to buy (you get discounts for bulk purchases), and whether you also want to purchase barcodes and/or QR codes from them.

Barcodes make it easier for retail shops to sell your books (just point and scan) while QR codes allow for reader interaction. You might set them up to have your readers directed to your author website, or to some exclusive bonus content. However, these are optional extras—they’re not necessary.

If you’re working with a tight budget, you can buy a single new ISBN number to start off; however, remember that each format of your book needs a separate ISBN. You’ll get a much better value if you buy ten ISBNs, which cost just over double the cost of a single number. With ten ISBN numbers, you’ll be able to release several formats of at least two novels.

After purchasing, your new ISBN number will be processed and ready within five days.

Getting an ISBN number in the United Kingdom and Ireland

Nielsen is the ISBN agency for the UK (including Scotland, Wales, and Northern Ireland) and the Republic of Ireland.

Just like the United States, the UK offers options to buy a single ISBN or ISBN numbers in bulk, which offer a better value; packs of ten are the most popular. These ISBNs cost roughly the same as those in the US.

Nielsen also offers barcodes and “Book2Look biblets” (similar to QR codes but fancier), which are interactive features that offer readers an inside look into your writing.

Their online shop offers two starter packages: the Self Publisher Pack and the Self Publisher Plus. The Self Publisher Pack contains one new ISBN, one barcode, one Book2Look biblet, and a year’s subscription to their enhanced marketing service. The “Plus” is the same format, only it offers ten ISBNs, ten barcodes, five Book2Looks, and a year’s subscription to their service. You might find that one of these packs is a great place to get started.

Once you purchase your chosen ISBN number or ISBN package, it will be processed in approximately five days.

Getting an ISBN number in Canada

Much like their enviable healthcare system, ISBN numbers are FREE to publishers and self-publishers in Canada.

First you’ll need to create an account with ISBN Canada. You only need to compete your ISBN registration once, and then you can apply for as many free ISBNs as you want.

You can request your free ISBN number with either an English-language code or a French-language code, and you need to provide proof of Canadian residency (sorry Yanks—no Friday-night drive bys). Once you fill out the form, your ISBN will be processed within ten days.

The Canadian free ISBN program, however, does not supply barcodes or interactive codes—you’ll need to find another source for those and order them separately.

Getting an ISBN number in Australia

Thorpe-Bowker is the official ISBN agency in Australia. They use a very similar system to Bowker in the US, and offer similar ISBN packages. Their pricing is substantially lower than their US counterparts; however, they do charge a first-time setup fee for new customers which the American Bowker doesn’t.

Ten-packs of ISBN numbers are their most popular option. They also sell barcodes, as well as ISBN/barcode package deals.

Thorpe-Bowker Australia does not list a processing time estimate, but their US counterpart quotes a wait time of five days.

Finding ISBN processes for your country

We’ve listed the major English-speaking countries and how you can find your local ISBN agency in each one. However, there are many more countries with their own ISBN agency. You can reach out to one of the one closest to where you live.

You can find the right agency for your particular country via the International ISBN Agency website. ISBN costs and processes can vary widely by country, so get in touch with your own ISBN agency and they can advise you on the next steps.

How much should you spend on an ISBN?

Depending on where you live, you might be able to get a free ISBN for your book. Other countries charge for them, but you can receive a better rate by purchasing several at a time.

At the time of writing, a single ISBN costs $125USD in the United States compared to $44AUD in Australia. A package of ten different ISBN numbers—which you can use for various formats and titles for as long as you need—cost $295USD or $88AUD, or approximately $30USD and $10AUD per number (although the Australian ISBN agency does charge that pesky setup fee!). In the UK, ISBNs cost £91 for a single ISBN and £169 for a block of ten.

ISBNs are a necessary expense of self-publishing.

As an emerging author, expect to spend around $100-$200 (or the equivalent in your home currency) on your first ISBN numbers.

While you can save some money only buying one ISBN to start off, it’s something of a false economy; you’ll inevitably need more later and wish you’d gotten a better value when you had the chance. Remember—every book format and new edition of the same book title needs its own ISBN number.

Larger quantities are designed with small-press publishers in mind. If you’re considering starting up your own publishing company, a pack of 100 ISBNs ($575 in the United States) is a good place to start; you can release several titles a year under several editions for the first few years.

Do ISBNs expire?

ISBNs do not expire—once you have one, it’s yours forever. They’re also firmly non-transferable within the book industry, which means you can’t sell it off or repurpose it for another book once you don’t need it anymore.

However, remember that you need a different ISBN for every version of your book. You can use the same ISBN if you catch a few typos in your first printing and promptly publish a new batch, but if your book undergoes a major revision, or if it’s released with new material, it will need an ISBN of its own.

For example, if you publish a “book club edition” of your book with extra author’s notes, interviews, and discussion questions, that book will need its own new edition ISBN—even if the old one and the new one are both paperbacks or both hardcovers.

Where will the ISBN appear on my book?

In a printed book, the ISBN should appear on the copyright page. All your books will have their own ISBN, but they’ll be different for different editions such as paperbacks, hardcovers, or rereleases.

Your ISBN will also appear on sales pages for various online bookstores. For example, if you’re selling a book on Amazon or other online retailers, the item listing will show the ISBN number. That way, potential readers know that they’re getting exactly the right edition they’re after.

ISBNs help potential readers track down your work!

Getting an ISBN for your book is quick and easy

An ISBN is the universal standard used by publishing companies to identify books. Getting an ISBN helps make it easier for you to enhance book sales and distribute across different markets, including your local library.

The process is quick and easy for self-publishing authors, and it brings you one step closer to selling your book to the largest possible audience!