What is an ISBN Number?

ISBN numbers are (almost) everywhere. If you pick up a book (even an audiobook) in-store or online then there’s a good chance you’ll have spotted a unique set of numbers beneath a bar code on the reverse. But what exactly are ISBNs? What does it stand for? And how did we come to use them in the first place?

What is an ISBN?

An ISBN or International Standard Book Number is defined by the International ISBN Agency as a number and not a barcode (the clue’s in the name really, otherwise we’d all be using the acronym ‘ISBBC’). ISBNs are used by libraries, publishers, and retailers the world over to easily identify the title of a book or similar book-like product. Despite the ‘B’ in ISBN standing for Book, the use of ISBNs also extends to certain CD, DVD, and video game formats, since these all need to be catalogued and identified as simply and as efficiently as possible in the world of publishing.

Where do ISBNs Come From?

So how long have ISBNs been around? Over forty years ago, the British retailer W. H. Smith announced plans to transfer its stock to a computerised warehouse and from there on, they needed a numbering system for all of their books, starting out with Standard Book Numbering or SBN. This successful system soon evolved to become international, and after worldwide committees were held in 1968 through to 1970, it was finally decided for the ISBN or International Standard Book Number to be approved. The ISBN standard hasn’t changed since and is still in use in over 150 countries today.

Where is the ISBN?

You can typically find ISBNs on the reverse of most books and book-like products on the bottom right or left-hand corner. The number itself can be between 10 and 13 digits in length depending on the year the product was published or manufactured. That’s why some of the older books or DVDs you decide to sell with us may have a shorter sequence of numbers or start with a different prefix set of digits compared with newer items. Up until December 2006, ISBNs used to be 10 digits in length, but as of January 2007, they have always consisted of 13 digits.

You may have noticed the number itself is split into five different sections. Each segment helps narrow down each element of the product’s identity – from its unique publisher and imprint, its geographical region and the specific edition or format of the book’s title, everything is carefully accounted for.

One wrong number can mean the difference between having your items go unrecognised by our system, so always be extra careful when typing in the unique ISBN. Downloading the WeBuyBooks app can help those with butterfingers by letting you scan the item’s barcode instantly and without error. Happy de-cluttering!