gtin-validator (npm): Utilities to validate and work with GTIN and UPC product codes.
Keywords: gtin|gtin-12|gtin12|gtin-13|gtin13|gtin-14|gtin14|valid|validation|validator|upc|upc12|upc-12|upc-8|upc8|upca|upc-a|upce|upc-e|ucc|ucc12|ucc-12|ean|ean-13|ean13|itf|itf13|itf-13|itf14|itf-14|product codes|jan|jan-13|jan13