Troubleshooting: Fix QR Codes That Won't Scan

Use these checks to diagnose and fix common scanning failures in printed QR codes.

1. Too small

Increase physical size. For hand‑held scanning, aim for at least 20–25 mm. Increase further for distance or dense content.

2. Low contrast

Use a dark foreground on a white background. Avoid light on dark and gradients inside modules.

3. Missing quiet zone

Ensure a clear white margin of at least 4 modules around the code. Nothing should intrude into this area.

4. Glare and reflections

Use matte finishes. Avoid glossy laminates or reflective foils that can confuse auto‑exposure.

Check for ink bleed or jagged edges. Prefer vector (SVG) in your layout or export high‑DPI PNG without resampling.

6. Camera focus and lighting

Test with multiple devices in realistic lighting. Ensure the camera can focus and the code fills enough of the frame.

7. Content is too dense

Shorten the content (e.g., branded short link) or increase the physical size and error correction.

8. Damage and obstructions

Increase error correction (Q/H) and overall size if the code may be scratched or partially covered. Keep logos small and centered.