Home · Compare · ISBN-10 vs ISBN-13: What's the Difference?
ISBN-10 vs ISBN-13: What's the Difference?
Same book, two formats — depending on when it was published. Here is the full breakdown.
ISBN-10 is the 10-digit International Standard Book Number format used from 1970 until December 31, 2006. ISBN-13 is the 13-digit format adopted on January 1, 2007 to align ISBNs with the EAN-13 barcode system. Every ISBN-10 has a direct ISBN-13 equivalent (with '978' prepended and a recalculated check digit), but new ISBNs since 2007 are issued only as ISBN-13.
Both formats identify the same book. ISBN-10 is technically deprecated for new publications, but books published before 2007 still display their original ISBN-10. Amazon's ASIN for paperback/hardcover books typically equals the ISBN-10 (for books published since 2007 that have an ISBN-13, Amazon converts back to ISBN-10 for the ASIN).
Bottom line
New publications (2007 onwards): always use ISBN-13. Looking up old books: search by ISBN-10 if that's what the book displays. Amazon ASIN for books: typically the ISBN-10 (Amazon converts ISBN-13 back to ISBN-10 if needed). Every book sold today has BOTH numbers, with the ISBN-13 being the official one.
ISBN-10 vs ISBN-13: side-by-side
| ISBN-10 | ISBN-13 | |
|---|---|---|
| Digits | 10 | 13 |
| Years used | 1970 – Dec 31, 2006 | Jan 1, 2007 – present |
| Prefix | No fixed prefix | 978 or 979 |
| Check digit | Mod-11 (can be 0-9 or 'X') | Mod-10 (always 0-9) |
| Barcode form | Bookland EAN with EAN-13 wrap-around | Direct EAN-13 encoding |
| Convertible? | Yes — to ISBN-13 by prepending 978 and recalculating | Convertible to ISBN-10 only if starting with 978 |
| Amazon ASIN equivalence | Yes — ASIN typically equals ISBN-10 | Amazon converts to ISBN-10 for ASIN |
| Issued today? | No — only legacy books | Yes — all new ISBNs are 13 digits |
How to convert ISBN-10 to ISBN-13
Three steps: (1) Prepend '978' to your 10-digit ISBN. (2) DROP the original check digit (the last character of the ISBN-10, which can be 0-9 or 'X'). (3) Calculate a new mod-10 check digit using the ISBN-13 algorithm. Example: ISBN-10 0306406152 → strip check digit → 030640615 → prepend 978 → 978030640615 → calculate new check = 7 → ISBN-13 9780306406157.
How to convert ISBN-13 to ISBN-10
Only possible if the ISBN-13 starts with '978' (the original Bookland prefix). Steps: (1) Drop the '978' prefix. (2) Drop the existing check digit. (3) Calculate a new mod-11 check digit using the ISBN-10 algorithm (the result can be 0-9 or 'X' representing 10). ISBN-13s starting with '979' CANNOT be converted — they have no ISBN-10 equivalent. Books published since 2020 increasingly have 979 prefixes as 978 runs out of capacity in some countries.
Why the switch happened in 2007
The 978 Bookland namespace was filling up — by the mid-2000s, certain country/language groups were nearly out of new ISBN-10 numbers. Switching to ISBN-13 doubled the available namespace (978 + 979 prefixes). Aligning with EAN-13 also simplified barcode systems — every ISBN became a standard EAN-13 retail barcode without special handling.
FAQ
Are ISBN-10 and ISBN-13 the same number?
Same book, different format. Every ISBN-10 has a corresponding ISBN-13 (with '978' prepended and a recalculated check digit). The reverse is only true for ISBN-13s starting with '978' — newer '979' ISBN-13s have no ISBN-10 equivalent.
Which ISBN should I use, ISBN-10 or ISBN-13?
For NEW publications: always ISBN-13 (it's the only format issued since 2007). For LOOKING UP old books: whichever format the book displays. For Amazon ASIN: typically ISBN-10 (Amazon's ASIN for books equals the ISBN-10). For most other systems: ISBN-13 is the official format.
How do I convert ISBN-10 to ISBN-13?
Three steps: (1) Prepend '978' to your 10-digit ISBN. (2) Drop the original check digit. (3) Calculate a new mod-10 check digit. Example: 0306406152 → 9780306406157. Many online converters do this automatically; our ISBN generator handles both formats.
Can ISBN-13 be converted to ISBN-10?
Only if the ISBN-13 starts with '978'. Steps: drop the 978 prefix, drop the existing check digit, calculate new mod-11 check digit. ISBN-13s starting with '979' cannot be converted to ISBN-10 — they have no equivalent.
When did ISBN-10 change to ISBN-13?
January 1, 2007. All ISBNs issued from that date onward are 13 digits with the '978' or '979' Bookland prefix. Books published before 2007 still display their original ISBN-10 and may not have a printed ISBN-13 even though one technically exists.
Does Amazon use ISBN-10 or ISBN-13?
Both, but ASIN typically equals ISBN-10. For paperback/hardcover books on Amazon, the ASIN is usually the 10-digit ISBN. For books published since 2007 that have only an ISBN-13, Amazon converts back to ISBN-10 for the ASIN. Kindle e-books get a B-prefix ASIN since they don't have ISBNs.
Related generators
Generate the right format now
Now that you know which one you need — render a valid barcode in seconds. No signup, no watermark, valid GS1 check digit. Free for casual use; paid plans from $9/mo.