Abstract
To allow the use of UPC barcodes on smaller packages where a full 12-digit barcode may not fit, a 'zero-compressed' version of UPC was developed called UPC-E.
This symbology differs from UPC-A in that it only uses a 6-digit code, does not use middle guard bars, and the end bit pattern (E) becomes 010101.
The way in which a 6-digit UPC-E relates to a 12-digit UPC-A is determined by the last (right-hand most) digit. With the manufacturer code represented by X's, and product code by N's then:
| Last digit | UPC-E equivalent is | UPC-A equivalent is |
|---|---|---|
| 0 | XXNNN0 | 0XX000-00NNN + check |
| 1 | XXNNN1 | 0XX100-00NNN + check |
| 2 | XXNNN2 | 0XX200-00NNN + check |
| 3 | XXXNN3 | 0XXX00-000NN + check |
| 4 | XXXXN4 | 0XXXX0-0000N + check |
| 5 | XXXXX5 | 0XXXXX-00005 + check |
| 6 | XXXXX6 | 0XXXXX-00006 + check |
| 7 | XXXXX7 | 0XXXXX-00007 + check |
| 8 | XXXXX8 | 0XXXXX-00008 + check |
| 9 | XXXXX9 | 0XXXXX-00009 + check |
For example a UPC-E barcode with the number 654321 would expand to the UPC-A 065100004327. You can convert UPC-E back to UPC-A using this web utility.
UPC-E check digits are calculated using this expanded string in the same way as used by UPC-A. The resulting check digit is not added to the barcode, however, but is encoded by manipulating the parity of the six digits which are present in the UPC-E - as shown in the following tables:
| Check digit | Parity pattern |
|---|---|
| 0 | EEEOOO |
| 1 | EEOEOO |
| 2 | EEOOEO |
| 3 | EEOOOE |
| 4 | EOEEOO |
| 5 | EOOEEO |
| 6 | EOOOEE |
| 7 | EOEOEO |
| 8 | EOEOOE |
| 9 | EOOEOE |
| Digit to be encoded | Odd parity pattern | Even parity pattern |
|---|---|---|
| 0 | 3-2-1-1 | 1-1-2-3 |
| 1 | 2-2-2-1 | 1-2-2-2 |
| 2 | 2-1-2-2 | 2-2-1-2 |
| 3 | 1-4-1-1 | 1-1-4-1 |
| 4 | 1-1-3-2 | 2-3-1-1 |
| 5 | 1-2-3-1 | 1-3-2-1 |
| 6 | 1-1-1-4 | 4-1-1-1 |
| 7 | 1-3-1-2 | 2-1-3-1 |
| 8 | 1-2-1-3 | 3-1-2-1 |
| 9 | 3-1-1-2 | 2-1-1-3 |
Our example code 654321, therefore, would become 1-1-1 4-1-1-1 1-2-3-1 2-3-1-1 1-4-1-1 2-2-1-2 2-2-2-1 1-1-1-1-1-1. The resulting barcode would look roughly like this:
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| 1.5.3. Prefixes |  | Chapter 3. Printing Considerations |
