1D vs 2D Encoding
Traditional barcodes encode data in one dimension — the width and spacing of parallel lines. They can typically store 8-25 characters. QR codes encode in two dimensions, achieving dramatically higher capacity in the same physical area. A QR code the size of a UPC barcode can hold 100x more data.
Error Tolerance
Traditional barcodes are fragile — a scratch across the bars, even brief, prevents scanning. QR codes have built-in error correction that allows recovery from up to 30% physical damage, making them far more suitable for harsh environments and outdoor use.
Scanning Requirements
Traditional barcodes typically require a laser scanner with precise alignment. QR codes can be scanned by any camera phone from any angle in any orientation. The finder patterns handle rotation. This accessibility made QR codes viable for consumer use.
Use Case Division
1D barcodes remain dominant for product identification in retail (UPC, EAN), inventory systems, and libraries. QR codes dominate for consumer-facing applications: mobile marketing, payment apps, boarding passes, menus, and any case requiring URL encoding.
Barcodes and QR codes are complementary technologies. QR codes win on capacity, error tolerance, and consumer scannability. Barcodes remain entrenched in retail infrastructure where they work perfectly.