QR Code Origins
- Invented: 1994 by Denso Wave (Toyota subsidiary) to track car parts in manufacturing
- Name: 'Quick Response'—designed to be scanned 10x faster than barcodes
- Patent: Denso Wave owns it but chose NOT to enforce it, enabling global adoption
QR Code Types This Tool Supports
- URL: Auto-opens website (most common use—menus, links, payments)
- WiFi: Scan to connect—perfect for guest networks, cafes, Airbnbs
- vCard: Scan to save contact—put on business cards, email signatures
- Email: Opens compose with pre-filled address (mailto: protocol)
- Phone: Tap to call (tel: protocol)
- SMS: Opens text message with pre-filled number and message
Error Correction Levels
- L (7%): Smallest QR, but easily damaged—use for perfect conditions
- M (15%): Default balance—handles minor scratches or dirt
- Q (25%): Good for printed materials that may get worn
- H (30%): Maximum recovery—allows logos in center (up to 30% can be obscured!)
Creative QR Code Uses
- Restaurant menus: COVID made these universal—no more sticky laminated menus
- Gravestones: QR codes linking to memorial websites with photos and stories
- Business cards: vCard QR saves your contact info with one scan
- WiFi sharing: Print and frame near your router for guests
- Scavenger hunts: Each QR reveals the next clue location
- Art installations: QR codes as design elements linking to artist info
Real-World QR Statistics
- 2022: 89 million US smartphone users scanned a QR code (up from 72M in 2019)
- China: QR payments processed $1.8 TRILLION in 2020 (WeChat Pay, Alipay)
- COVID impact: Restaurant QR menu usage jumped 750% in 2020
- Maximum capacity: 4,296 alphanumeric characters (or 7,089 digits)
- Smallest readable: About 1cm × 1cm for simple URLs (10 modules wide minimum)
QR Code Best Practices
- Test before printing: Scan with multiple phones and apps
- Quiet zone: Leave white border around QR (at least 4 modules wide)
- Contrast matters: Dark foreground on light background works best
- Size rule: 10× the scanning distance in mm (10cm away = 1cm QR minimum)
- Short URLs: Use URL shorteners for complex links—simpler QR = more reliable
- Track scans: Use UTM parameters or QR analytics services
QR vs Other Codes
- Barcode: 1D, holds ~20 chars, requires laser scanner
- QR Code: 2D, holds ~4,000 chars, any camera works
- Data Matrix: 2D, smaller than QR for same data, used in electronics/pharma
- Aztec Code: 2D, no quiet zone needed, used in airline boarding passes