QR (Quick Response) codes are two-dimensional matrix barcodes invented in 1994 by Denso Wave, a subsidiary of Toyota. Unlike traditional linear barcodes, QR codes can store significantly more information and can be read from any direction.
How QR Codes Work
QR codes use a grid of black and white squares to encode data. The pattern includes:
- Position Markers: Three large squares in corners for orientation
- Timing Pattern: Alternating modules to determine symbol size
- Data Area: The encoded information in matrix format
- Error Correction: Reed-Solomon codes for data recovery
Technical Specifications
- Numeric: 7,089 characters
- Alphanumeric: 4,296 characters
- Binary: 2,953 bytes
- Kanji: 1,817 characters
- L (Low): ~7% recovery
- M (Medium): ~15% recovery
- Q (Quartile): ~25% recovery
- H (High): ~30% recovery
QR Code Versions
QR codes come in 40 different versions, ranging from Version 1 (21×21 modules) to Version 40 (177×177 modules). Higher versions can store more data but require more precise printing and scanning.