The maxicode barcode is identified by the circular bulls-eye in the center and a matrix of circular dots that make up the data. Unlike many of the other 2D barcodes, this symbology uses a hexagonal grid rather than bars or squares.
These symbols are always printed as a 1 inch square often found on shipping packages and can store around 93 characters. If more data is needed, up to 8 codes can be chained together and scanned one after the next. The bulls-eye helps the scanner identify the pattern even when packages are streaming by at speed.
There are several modes that these symbols can use. UPS uses mode 2 and 3 on their packages.
- Mode 0 - Obsolete mode superseded by modes 2 and 3. (Older printers will produce Mode 0 if the firmware is outdated. Mode 0 MaxiCodes can be visually determined by examining the two horizontal hexagons in the upper right-hand corner. They will be white if the Mode is 0. For all other modes, they are black.)
- Mode 1 - Obsolete mode superseded by mode 4.
- Mode 2 - Formatted data containing a structured Carrier Message with a numeric postal code. (Primary use is US domestic destinations.)
- Mode 3 - Formatted data containing a structured Carrier Message with an alphanumeric postal code. (Primary use is international destinations.)
- Mode 4 - Unformatted data with Standard Error Correction.
- Mode 5 - Unformatted data with Enhanced Error Correction.
- Mode 6 - Used for programming hardware devices.
If you need to generate your own maxicode barcodes, you can check out the bcgen.com web site.