QR

Before Generating

1. Choose correct type — URL is not the only option. See types.md for vCard, WiFi, email, SMS, geo, etc.
2. Shorten dynamic URLs — Long URLs = dense codes = harder to scan. Use short links for tracking too.
3. Set error correction — L (7%) for clean environments, M (15%) default, Q (25%) with logos, H (30%) for harsh conditions

Sizing Rules

Minimum sizes by scan distance:

• Phone at arm's length (~30cm): 2x2 cm minimum
• Table tent (~50cm): 3x3 cm
• Poster (~1m): 5x5 cm
• Billboard (~5m): 25x25 cm

Formula: QR size = scan distance ÷ 10

Color & Contrast

• Minimum 70% contrast between foreground and background
• Dark on light ONLY — scanners expect dark modules
• Never invert (white on black fails on many readers)
• Avoid gradients on modules — solid colors only
• Background can have subtle texture if contrast maintained

Testing Checklist

Before printing/deploying:

• Scan with 3+ different phones (iOS, Android old/new)
• Test in target lighting conditions
• Verify destination loads correctly
• Check at actual print size, not screen preview
• Test after any logo/customization applied

Common Failures

Use Case Guides