QR codes include redundant data so scanners can recover if part of the pattern is dirty, folded, or covered. That redundancy is called error correction, standardized in four levels: L, M, Q, and H.
Error correction levels explained
| Level | Recovery | Typical use |
|---|---|---|
| L (Low) | ~7% damage | Clean digital displays |
| M (Medium) | ~15% damage | General print default |
| Q (Quartile) | ~25% damage | Industrial labels |
| H (High) | ~30% damage | Codes with center logos |
Trade-off: density vs durability
Higher correction adds more modules — the pattern gets denser and may need slightly larger print size. A centered logo eats modules; use level H if branding requires it. Test scans after adding artwork — color and logo tips.
What error correction cannot fix
- Wrong or dead URL encoded in the QR
- Extreme blur or low contrast
- Quiet zone clipped by design
- Code printed far below minimum size
QRCode Lab picks sensible defaults for marketing print. For damaged physical codes, see fixing broken QR codes. Generate codes with appropriate correction for your creative.