Direct comparison
ISBN-13 vs ISBN-10: What Changed in 2007
ISBN 13 vs 10: ISBN-10 ended in 2006, ISBN-13 is the only current form, and 979 numbers have no 10-digit equivalent. See what differs and what to record.
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How do ISBN-10, ISBN-13 compare side by side?
The table below compares ISBN-10, ISBN-13 across 10 procurement-relevant dimensions, from length and period of use through source.
Side-by-side comparison
| Dimension | ISBN-10 | ISBN-13 |
|---|---|---|
| Length and period of use | Ten digits. ISBNs were 10 digits long up to the end of December 2006. | Thirteen digits. Since 1 January 2007 ISBNs always consist of 13 digits. |
| Status today | Legacy. The Agency says 10-digit ISBNs should no longer be quoted. | The only current form; every newly assigned ISBN is 13 digits. |
| Prefix element (978 and 979) | A 979 ISBN has no equivalent 10-digit ISBN, so ISBN-10 cannot represent it. | The prefix element is 3 digits and currently either 978 or 979. 979-8 is unique to the United States and its associated territories. |
| Check digit | Converted by the Agency calculator into the correct 13-digit number rather than checked by hand. | The final single digit, calculated using a Modulus 10 system with alternate weights of 1 and 3. |
| Converting between them | Convert up with the Agency ISBN calculator, which turns old 10-digit ISBNs into their 13-digit counterparts. | Old 10-digit numbers convert up to it. A 979 number has no 10-digit equivalent, and forcing a conversion down causes serious errors, including duplicated ISBNs. |
| What to record and send to partners | Do not use it as the stored or exchanged identifier. | The Agency states that all ISBNs must be recorded in all systems and communicated to partners only in their complete 13-digit form. |
| One book, several numbers | A legacy number identifies the same thing as its 13-digit counterpart. | Each product form still gets its own ISBN, so one title can legitimately carry several ISBN-13s; the publication element identifies the edition and format. |
| Use as an ISBN-A (DOI form) | Not eligible; it must be converted to 13 digits first. | Eligible. An ISBN-A is a 13-digit ISBN expressed in DOI syntax. |
| When to pick each | Only to read an older catalogue record, receipt or citation, then convert it to ISBN-13. | For cataloguing, citing, depositing and any exchange of records between systems. |
| Source | International ISBN Agency, 'What is an ISBN?' and ISBN calculator (isbn-international.org), read 2026-10-29. | International ISBN Agency, 'What is an ISBN?' and 'Changes to United States ISBN prefixes' (notice dated 2019-11-29), read 2026-10-29; doi.org ISBN factsheet for ISBN-A. |
Common questions
Common questions about ISBN-10 vs ISBN-13
ISBN 13 vs 10: what is the difference?
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Length and era. ISBN-10 was the 10-digit form used up to the end of December 2006. Since 1 January 2007 ISBNs always have 13 digits, with a 978 or 979 prefix element in front. The 13-digit form is the only current one.
ISBN-13 vs ISBN-10: which one should I use?
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Use the ISBN-13. The International ISBN Agency says 10-digit ISBNs should no longer be quoted and that ISBNs must be recorded and communicated to partners only in their complete 13-digit form.
Can every ISBN-10 be converted to an ISBN-13, and the other way round?
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Every old 10-digit ISBN can be converted up with the Agency calculator. The reverse is not true: a 979 ISBN has no equivalent 10-digit ISBN, and converting one down causes serious errors including duplicated ISBNs.
How does the ISBN-13 check digit work?
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It is always the final single digit and mathematically validates the rest of the number. For ISBN-13 it is calculated using a Modulus 10 system with alternate weights of 1 and 3.
Does an ISBN-10 or ISBN-13 identify the book or the edition?
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The edition and format. Each different product form, such as paperback, EPUB or PDF, should be identified separately, so one title can have several ISBN-13s.
What is the difference between ISSN and ISBN?
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An ISBN identifies a specific edition and format of a book; an ISSN identifies a serial such as a journal. The full comparison, including how the two are assigned, is in the ISBN vs. ISSN comparison.
