Choosing the right error correction level
Error correction level determines how much damage or obstruction a QR code can sustain while still being scannable. Higher correction = more resilient code, but also a denser pattern.
The four levels
| Level | Recovery capacity | Best for |
|---|---|---|
| L (Low) | ~7% | Digital screens, clean environments |
| M (Medium) | ~15% | General use — the default |
| Q (Quartile) | ~25% | Industrial, slightly rough environments |
| H (High) | ~30% | Codes with a logo, or harsh conditions |
When to use each level
- L — digital use only (website, email, presentation). Smallest, cleanest pattern.
- M — general print use. Good balance of density and resilience.
- Q — industrial use, product packaging, or environments where codes may get dirty.
- H — any code with a logo. Required for logo embedding to work reliably.
ℹ️ Unqode SmartQR automatically upgrades to Level H when you add a logo. You don't need to manually select it.
Does a higher level mean slower scanning?
Not noticeably. Modern QR scanners handle all levels equally fast. The trade-off is visual density — H level codes have more modules (smaller squares) and can look busier. For very small print sizes, M or L may scan more reliably than H.