UPC bar codes are used in the United States of America. Like many other kinds of bar codes, they are made up of numbers. The scanners interpret these symbols and the data is sent into the system. All American products get either UPC - A or UPC - E bar codes. The bar code generators are also capable of generating 2- to 5-digit supplemental codes.

A UPC-A bar code consists of 12 digits, and a UPC - E bar code consists of 8 digits. The UPC bar codes are numeric-only codes that may vary in height, width and spacing to represent various item codes. UPC bar codes include the checksum bar at the end of the code as the last digit. The checksum calculation used in the UPC bar codes is complex compared to other bar codes, but it is wise to include it in the bar code.

UPC bar code software suites are similar to other bar code software suites. They include the entire font, templates and other options that allow the user to generate a code and allow VBA functions for spreadsheets and database utility. Almost all of these software suites are equipped with the BARUP.exe that is essential to calculate checksum and formatting of the UPC bar codes, along with the checksum option.

UPC bar codes do not have the actual price of an item, similar to other codes. They are coded with the specific item code whose value would be picked by the software from the database consisting of all such related data.

Any manufacturer needing to get a bar code for a new product needs to get a manufacturer number from the Uniform Code Council. The manufacturer then assigns the product number. A combination of the manufacturer number and the product number makes the number for the bar code. It must be ensured that this number is equal to 11 digits, as the 12th digit would be the checksum code. Each product can thus be given an individual and unique UPC code as the manufacturer can decide the second half of the bar code even though the first half, which is the manufacturer number, is the same for all the items made by that manufacturer.

UPCTools is one option to make a UPC bar code. Also, their plug-ins can be used to make multiple UPC bar codes in no time. This software would help with the design of the bar code and also generates the checksum amount automatically. As with other bar code generators, this can be used to create a unique bar code complete with the start, stop and checksum bars within the bar code. The same can be used to define the height and size of the bar code, depending on the product that needs to be labeled.