Lección 2
Error Correction Levels en español
Guía en español para qr code qr error correction levels: L, M, Q, and H—and the redundancy trade-off.
Este contenido todavía no está disponible en español. Se muestra la versión en English mientras completamos la localización.
QR codes include error correction codewords so scanners can recover when part of the symbol is dirty, creased, or covered.
The four levels
| Level | Approx. recovery | Typical use |
|---|---|---|
| L | ~7% | Maximum data capacity; clean, large display |
| M | ~15% | Default for everyday URLs and short text |
| Q | ~25% | Small print, partial obstruction |
| H | ~30% | Center logos, worn labels, harsh environments |
Higher correction adds redundancy. The symbol becomes denser for the same payload—long strings may fail to encode at high levels within a reasonable module count.
Trade-offs developers feel
- More data → prefer L or M
- Smaller print or partial cover → prefer Q or H
- Generation errors in browser tools → shorten text or drop a level
Percentages describe how much damage may be recoverable—not a guarantee under every camera and lighting condition.
Not a substitute for design
Error correction helps damaged symbols. It does not fix:
- Low contrast (light gray on white)
- Missing quiet zone (margin) around the code
- Extreme blur or glossy reflections
Key takeaway
Pick M when unsure. Raise to Q/H when physical damage or obstruction is likely—not because "more correction is always better."