UPC-A Barcode Introduction

UPA-A barcode is continuous, self-checking, numeric-only, and omni-directionally decodable. It has one mandatory check digit and encodes numeric digits only. A UPC-A barcode may be accompanied by a 2-digit or 5-digit Add-On Symbol. UPC-A symbol is widely used in North America for consumer goods.

Encodable Chars	UPC-A symbology encodes 12 numeric digits (including checksum) through 0 to 9.
Checksum Digit	Though UPC-A is character self-checking, a mandatory modulo 10 check digit is required in the standard. Our product will add the checksum automatically according to the standard.
Components	Number System is encoded in the first digit placed with the corresponding human-readable in the left, followed by the four digits of Manufacturer Code, then the four digits of Product Code, and lastly the Check Digit.
Add-on Symbols	A two-digit or five-digit add-on symbol can be added to a UPC-A symbology to encode supplementary information.
Guard Bar Pattern	The UPC-A data is separated by two Normal Guard Bar Pattern, which are encoded as 101, and a Center Guard Bar Pattern encoded as 01010.

 

Quiet Zone	Guard Bar Pattern	6 Data Chars	Center Guard Bar Pattern	6 Data Chars	Guard Bar Pattern	Quiet Zone
1	2	3	4	5	6	7

To set the size of UPC-A, two things are of importance, i.e. the X Dimension and the barcode width.
Click here for more information on UPC-A size setting.