MaxiCode: O código de barras em cada encomenda UPS

MaxiCode: The Barcode on Every UPS Package

MaxiCode is a 2D barcode symbology developed by UPS in 1992 for high-speed parcel sorting. Its distinctive hexagonal grid and central bull's-eye finder pattern make it instantly recognizable on UPS shipping labels worldwide.

Unique Design

MaxiCode uses a fixed-size symbol of approximately 25.4mm x 25.4mm (1 inch square) containing:

• Central finder pattern: Three concentric hexagonal rings (bull's-eye)
• Data area: 866 hexagonal modules arranged in 33 rows around the finder
• Orientation patterns: Three small patterns for rotational alignment

Unlike other 2D codes, MaxiCode uses hexagonal modules instead of square ones, and its size is fixed rather than variable.

Data Capacity

These limits are modest compared to Data Matrix or QR Code, but sufficient for the shipping data MaxiCode was designed to carry.

Operating Modes

MaxiCode defines six modes, of which three are in active use:

• Mode 2: Structured carrier message (US addresses) - primary and secondary data
• Mode 3: Structured carrier message (international addresses)
• Mode 4: Standard symbol with error correction (general use)
• Mode 5: Full ECC (maximum error correction)
• Mode 6: Scanner programming (not for data)

Modes 2 and 3 split data into a primary message (postal code, country code, service class) and a secondary message (tracking data, address details). This structure enables high-speed sorting by reading only the primary message.

Error Correction

MaxiCode uses Reed-Solomon error correction:

• Primary message: Can correct up to 2 codeword errors
• Secondary message: Can correct up to 12 codeword errors (standard EC) or 28 (enhanced EC)

UPS Usage

Every UPS package label includes a MaxiCode that encodes:

• Ship-to postal code
• Country code
• Service class
• Tracking number
• Ship-to address details

UPS hub sorting systems read MaxiCode at speeds of up to 100 feet per second on high-speed conveyor belts. The fixed symbol size and distinctive finder pattern enable reliable reading at these speeds.

Specifications

Current Status

MaxiCode was adopted as ISO/IEC 16023. While UPS continues to use it, the broader logistics industry has largely standardized on Code 128, GS1-128, and Data Matrix for package labeling. MaxiCode remains primarily a UPS-specific symbology.