ISBN barcode generator

An ISBN barcode is an EAN-13 carrying a book number instead of a grocery one. Since the thirteen-digit ISBN arrived, the number on the copyright page and the number under the bars are one and the same string: nothing is prefixed, nothing is recalculated, and the hyphens in a printed ISBN are punctuation for people rather than data. Thirteen digits go into the field and those same thirteen digits come out under the symbol. What the field cannot tell you is whether they are yours.

Appearance
Size
Caption
Caption position
Caption alignment
Colours

340 × 244 px in the PNG

Size units

Specification

Character set
digits
Length
exactly 13 characters
Check digit
calculated automatically by the encoder

Got a whole list of values rather than one? Generate ISBN barcodes in bulk

Where it is used

  • Back-cover artwork on its way to a printer, where the symbol has to sit in the layout as a vector and not as a screenshot of one
  • A second binding or a revised edition, each of which carries its own ISBN and therefore its own symbol, even when the text between the covers is untouched
  • Rebuilding a cover that survives only as a flattened image, where the thirteen digits are still legible but the barcode has to be drawn again
  • Checking a number copied off a printed book before it goes into a catalogue record or a supplier feed

How it compares

Against the EAN-13 page there is nothing technical to report: the same ninety-five modules of bars, the same mod-10 check digit, the same behaviour at the till. Everything that separates them happens before the artwork. Every other retail number descends from a GS1 company prefix; an ISBN descends from the ISBN agency of the country the publisher is based in, working under the International ISBN Agency, and GS1 issues no part of it. What GS1 contributed was the reservation itself — 978, and later 979, set aside for the book trade so that book numbers and grocery numbers could share one scanner without ever colliding. The second difference is historical and still turns up in old files. A ten-digit ISBN was never the number in the barcode. The symbol was assembled: throw away the ten-digit check character, put 978 in front of the nine digits left, compute a fresh check digit at the end. Since the thirteen-digit form took over, that assembly step is gone, and it only ever ran in one direction — a 979 number has no ten-digit equivalent, which is the whole reason 979 was opened once 978 started to run out.

Common mistakes

  • Expecting this page to tell you the number is an ISBN. It tests two things and stops: thirteen digits, and a thirteenth that agrees with the other twelve. Paste in an ordinary retail number such as 5901234123457 and the status line reports the value as valid and the symbol is drawn, because as an EAN-13 it genuinely is valid — it is simply not a book. Reading the first three digits and confirming they are 978 or 979 is a check you make, not one the field makes for you.
  • Typing the ISBN the way it is printed on the copyright page. Hyphens are not part of the number and the field will not take them: paste 978-0-000000-00-0 and validation stops at the first one, reporting that the character is not allowed at position 4. Remove every hyphen and the identical number goes straight through. Nor can they be put back mechanically afterwards — where the hyphens fall depends on how many digits the registration group and the registrant element each occupy, and those lengths differ from one publisher to the next.
  • One number stretched across formats. Paperback, hardback, ebook and audiobook are four products and take four ISBNs, and because the barcode is the ISBN, no single symbol can cover the set. The reverse error is just as common: a straight reprint from unchanged files is the same product and keeps the number it already has.
  • Accepting a free ISBN from a publishing platform without reading what comes attached. The agency record behind a number names a publisher, and that record is what wholesalers, libraries and retailers read back. A number issued to you through a platform names the platform in that field, and the entry is not something you edit later by moving the book to a different printer or a different distributor.

Frequently asked questions

Is the number in the barcode the same as the ISBN?
Yes. The thirteen digits of the ISBN, with the hyphens taken out, are exactly what the bars encode — there is no second number to look up or derive. That was not true in the ten-digit era, and a good deal of the confusion sitting in old cover files dates from then, when the printed ISBN and the barcode number really were two different strings.
How do I turn a ten-digit ISBN into the thirteen-digit one?
Drop the last character of the ten — it comes from a modulo-11 calculation, which is why it is sometimes the letter X, and it has no place in the new number. Put 978 in front of the nine digits that remain and you have twelve. Type those twelve into the field and the status line prints all thirteen with the last one already calculated, ready to copy back. Feed the ten digits in unchanged and you get a plain length complaint with no suggestion attached, because the field only offers to compute a check digit when the value is exactly one digit short.
What about the small price block printed to the right of the bars?
Not from this field, which takes thirteen digits and nothing else. That block is a separate symbol printed alongside the main one, and its five digits are a currency indicator followed by a four-digit price — 5 for US dollars, for instance — with the value 90000 used by convention to say that no price is encoded. Because it is separate, a publisher can change it between printings without reissuing the ISBN, which is the practical reason to encode 90000 on a title whose price is not yet settled.
Where does an ISBN come from, and does GS1 sell them?
GS1 does not. You apply to the ISBN agency for the country the publishing imprint is based in, and those agencies are national bodies coordinated by the International ISBN Agency rather than branches of one company. What it costs and whether you can buy a single number or only a block depends entirely on which agency that is — some issue them at no charge, others sell them in ranges. The registration is the point of the exercise: it is what puts your imprint against the number in a database that the trade queries, and the barcode is only the printed consequence of it.
Does an ebook need a barcode?
It needs an ISBN if you want it listed and ordered like a book, but a barcode is a way of scanning a physical object and an ebook is not one. Assign the number, put it in the metadata, and skip the symbol. The place this matters is print-on-demand hybrids, where the same title exists in both forms — the printed edition gets its own ISBN and a barcode on the cover, and reusing the ebook's number for it is the mistake.

This generator draws a valid ISBN symbol, but the image alone does not grant the right to sell a product under it in retail. The prefix is issued by ISBN Agency — register it there before printing this code on packaging.