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Barcode Info > UPC-A
Linear Barcode
Code 39
Code 128
EAN 128
UPC-A Barcode Symbology Overview
UPC-A barcode character set, checksum and structure & recommended barcode library for ASP.NET, Winforms, Word and Excel
UPC-A Barcode Introduction
The barcodes utilized by GS1 include EAN/UPC, GS1 DataBar, GS1-128, ITF-14, GS1 DataMatrix, and Composite Component. A trade item that is intended to cross the Point-of-Sale in a retail outlet must carry a bar code symbol, allowable symbols are EAN-13 and UPC-A. UPC-A was used to encode GTIN-12, Coupon-12, RCN-12, and VMN-12. UPC-A is an subset of EAN-13 and is widely used on books, CDs and newspapers. Each UPC-A encodes 11 digits into a symbol and addpended with checksum digit which makes the total length to be 12 digits long. UPC-A uses a two/five-digit Add-On Symbol to encode information supplementary to that in the main barcode symbol.
UPC-A Barcode Generator for .NET Applications provides complete solution for UPC-A barcode generation in ASP.NET, Windows Forms application and other .NET environment.
Detailed Information for UPC-A and UPC-A Supplementary Barcodes

UPC-A Structure

The UPC-A barcode symbology should compose of 4 parts, among which are number system to identify the product type, the manufacturer code uniquely assigned by UCC council, the product code encoded in UPC-A and the checksum digit. UPC-A barcode symbology is represented as black bars and white spaces. When supplemental digits considered, it should be appended following the right Quiet Zone of UPC-A barcode symbology.

Modulo 10 checksum digit

Like barcode EAN-8, UPC-A utilizes the modulo 10 calculation formula to compute the check digit. It is essential to employ the checksum digit since it offer detection for scanning the barcode. It is easy to compute checksum digit of UPC-A, just follow the steps:
For example, the check digit of "15896324895 " is 0.