ISBN Barcodes for Books: A Guide for U.S. Self-Publishers

An ISBN-13 is already a barcode number

An ISBN identifies one edition of a book, from one publisher, in one format. Since January 1, 2007, national agencies have issued only 13-digit ISBNs, each made of five parts, according to the International ISBN Agency's ISBN Users' Manual. Here they are in the widely used example ISBN 978-0-306-40615-7:

GS1 lists 978 and 979 as "Bookland (ISBN)" in its prefix table, and the GS1 General Specifications name the ISBN as the recommended way to identify books scanned at retail. The book trade calls the resulting barcode the Bookland EAN. It's the same EAN-13 symbol used on other retail products, compared in UPC vs. EAN, and its number is simply the ISBN-13 without hyphens.

The General Specifications also rule out ISBNs for non-book products, even a mug or T-shirt tied to a book launch. Those need a regular GTIN.

Who issues ISBNs in the United States

The International ISBN Agency lists R.R. Bowker as the U.S. ISBN agency. Bowker sells ISBNs through its MyIdentifiers site. The ISBN manual adds that you get ISBNs from the agency where you, the publisher, are based, wherever your printer or self-publishing platform happens to be.

As of October 2026, Bowker's ISBN price list shows one ISBN for $125, 10 for $295, 100 for $575 and 1,000 for $1,500. Prices change, so check the page before you buy. This is general information, not legal or financial advice.

Count formats, not titles. The manual requires a separate ISBN for each format and edition, so a paperback, a hardcover and an EPUB of the same book need three. A new cover design or a price change doesn't require a new ISBN.

Free platform ISBNs

KDP offers free ISBNs for paperbacks and hardcovers, but its ISBN help page says they can only be used on KDP, and the imprint appears as "Independently published." The ISBN manual makes the general point: when a service provider assigns one of its own ISBNs, the provider is likely to be listed as the publisher. If you plan to sell the same edition through other channels, an ISBN in your own name saves a number change later.

Don't buy ISBNs secondhand, either. The manual says a publisher can't resell, transfer or split its ISBNs among other publishers.

Converting an ISBN-10 to ISBN-13

Many books published before 2007 carry 10-digit ISBNs. The International ISBN Agency says these should no longer be quoted and should be converted to their 13-digit form (ISBN Calculator). The UK ISBN agency's FAQ gives the method: put 978 in front, then recalculate the check digit with the modulus 10 method and alternating weights of 1 and 3.

Here's the conversion of ISBN-10 0-306-40615-2:

1. Drop the old check digit, the final 2: 030640615.
2. Put 978 in front: 978030640615.
3. Weight the 12 digits 1, 3, 1, 3 and so on from the left. The digits in odd positions (9, 8, 3, 6, 0, 1) add up to 27. The digits in even positions (7, 0, 0, 4, 6, 5) add up to 22, and 22 × 3 = 66.
4. Add the two results: 27 + 66 = 93.
5. Subtract the last digit of the total from 10: 10 − 3 = 7. If the last digit is 0, the check digit is 0.

The result is ISBN 978-0-306-40615-7. The check digit changed from 2 to 7 because ISBN-10 used a different formula, which is also why some old ISBNs end in X; a 13-digit ISBN never does.

Only ISBNs starting with 978 have a 10-digit twin. The Book Industry Study Group (BISG) notes there's no ISBN-10 equivalent for an ISBN starting with 979. To double-check a result, the check digit calculator validates any ISBN-13 as a GTIN-13, and how check digits work explains why the weighting catches typos.

The 5-digit price add-on

On many U.S. books you'll see a shorter barcode to the right of the main one. It's a 5-digit add-on, often called EAN-5. BISG's barcoding guidelines describe the full Bookland EAN as the 13-digit ISBN plus this separate price add-on, and the ISBN manual says using it for price is a U.S. and Canadian practice.

For prices up to $99.98, the first digit is a currency indicator, 5 for U.S. dollars, and the other four digits are the price with an implied decimal point. BISG has since added prices from $100.00 to $499.99, written with all five digits. BISG's table:

GS1 treats the add-on as extra data. It isn't needed to identify the title, and reading it at the register is optional, per the General Specifications. It has no separate check digit; the pattern of its bars carries a built-in check instead.

Should you include a price? BISG says some retailers and publishers require the price extension, and asks publishers to talk with their trading partners before leaving it out. If you don't encode a price, BISG recommends 90000. If you do, it has to match: KDP's barcode rules say the price code should match your list price. When the price changes, the ISBN stays the same, but the add-on, and with it the barcode, must be redone.

Placing and sizing the barcode on the cover

BISG puts the barcode at the bottom of the back cover, with the bottom of the symbol 1/4 inch above the bottom edge, and the ISBN manual recommends the lower right, near the spine. Print the ISBN directly above the bars, starting with the letters ISBN, for example ISBN 978-0-306-40615-7. BISG asks for 9-point type or larger, in a sans-serif font such as OCR-B or Arial.

BISG's size and print rules:

• At 100% magnification, the barcode with its add-on is 1 inch high and 2-3/16 inches wide. Anything from 80% to 200% is allowed.
• Don't shorten the bars, and don't draw a border around the barcode.
• Print the bars in black or dark blue on white, yellow or red. Never reverse the colors.
• Keep the clear space to the right of the add-on. Book barcodes often print a ">" there to protect it.

KDP has its own barcode requirements for covers you upload: a suggested area of 2 × 1.2 inches (minimum 1.4 × 0.8 inches), at least 0.25 inch from the spine and trim, 100% black bars on a solid white background, and vector art or a 300 PPI image. If your cover has no barcode, KDP adds one at no extra cost. For bar width, quiet zones and test printing in general, see how to print barcodes that scan.

Making an ISBN barcode with the generator

BISG says publishers can make their own barcodes with software, as long as the result meets industry specifications and the ISBN passes its check-digit test. Plain Barcode's barcode generator has an ISBN type for this. Type the ISBN-13, then a space and the add-on, such as 978-0-306-40615-7 51499, or 90000 for no price. The add-on is optional. If you type an ISBN-10, the generator checks it and converts it to ISBN-13, and it always checks the ISBN-13 check digit.

It draws the EAN-13 with the add-on to its right at GS1's nominal size: a 0.330 mm X-dimension and 22.85 mm bars. Download the SVG to place it at exact physical size in your cover software, or a PNG made for a 300 or 600 dpi printer. Then set the human-readable ISBN line above the bars in your layout.

It won't issue or register ISBNs, or grade print quality. The number itself has to come from your ISBN agency.

Next step

Get your ISBN from Bowker, or confirm the one you already have, and ask your retail channels whether they want a price in the add-on. Then make the barcode with the ISBN type in the barcode generator, place it at the lower right of the back cover, and scan a 100% proof before you send the files to print.