Since I have done this research on my own, which I did in 1996, I have come across other websites that explain the concepts quite well. This one, in particular, does a great job. I would update this page, but you can just go there and save me the time.
This document is to be used for informational purposes only. DO NOT use this information in order to produce fraudulent barcodes. Do not attempt to use fraudulent barcodes to purchase goods at extremely low costs.
Method for forming standard UPC bar codes:
1) Bar code must begin with the start sequence.
2) The first 6 digits use the “Left Side” codes.
3) After 6 digits, the middle sequence must be inserted.
4) The last 6 digits use the “Right Side” codes.
5) Bar code must end with the end sequence.
Notes:
– Standard UPC bar codes consists of 12 digits.
– Each 1 stands for a line of the standard width.
– Each 0 stands for an empty space of the standard width.
– 1 pixel wide is an acceptable standard width for functional barcodes.
| Left Side | Right Side | |
| 1) 0110010 | 1) 0110011 | |
| 2) 0100110 | 2) 0110110 | |
| 3) 1111010 | 3) 0100001 | |
| 4) 1000110 | 4) 0101110 | |
| 5) 1100010 | 5) 0100111 | |
| 6) 1011110 | 6) 0101000 | |
| 7) 1110110 | 7) 0100010 | |
| 8) 1101110 | 8) 0100100 | |
| 9) 0010110 | 9) 0111010 | |
| 0) 0011010 | 0) 0111001 |
| Start: | 1010 | |
| Middle: | 101 | |
| End: | 0101 |
DO NOT Attempt to use this example barcode to purchase expensive goods at the price of Lemonade Kool-Aid (about $0.25) by printing it out and taping it over a real UPC barcode.
