How EAN and UPC numbers relate
All four are GTINs (Global Trade Item Numbers). A UPC-A is a 12-digit GTIN; written with a leading 0 it becomes the equivalent 13-digit EAN-13, and the barcodes are identical. That's why a scanner may show a UPC-A as a 13-digit number starting with 0. EAN-8 is a separate, shorter number issued for small packages. It isn't a shortened EAN-13.
When can a UPC-A be shortened to UPC-E?
Only UPC-A numbers with number system 0 or 1 and zeros in particular positions. The pattern is recorded in the last digit of the UPC-E (before the check digit):
| UPC-E ends in | Required zeros in the UPC-A |
|---|---|
| 0, 1, 2 | The manufacturer code ends in that digit then 00, and the item number starts with 00. |
| 3 | The manufacturer code ends in 00, and the item number starts with 000. |
| 4 | The manufacturer code ends in 0, and the item number starts with 0000. |
| 5–9 | The item number is 0000 followed by that digit. |
Most UPC-A numbers don't fit any of these patterns, so they can't be printed as UPC-E.
What prefixes tell you
- 978 or 979: a book (ISBN); 979-0 is printed music (ISMN).
- 977: a magazine or other periodical (ISSN).
- 20–29, and UPC number systems 2 and 4: restricted circulation numbers for in-store use, such as weighed goods.
- Other prefixes show which national GS1 organisation issued the company's prefix. They don't reveal where a product was made.