Universal Product Code - Numbering

Numbering

UPC-A and UPC-E each provide a theoretical maximum of 1 trillion (10^12) unique barcodes, though in practice the number of barcodes is limited by the standards used to create them.

UPC-A: (10 possible values per digit ^ 6 left digits) × (10 possible values per digit ^ 6 right digits) = 1,000,000 × 1,000,000 = 1,000,000,000,000.
UPC-E: 10 possible values per digit × 2 possible parities per digit = 20 permutations per digit ^ 6 digits = 64,000,000.