Choosing the Right QR Error Correction Level (L/M/Q/H)

One of the most powerful — and least understood — features of QR codes is error correction. It allows a QR code to be scanned even if damaged, dirty, or partially covered (like with a logo).

There are four levels: L, M, Q, and H. Each trades data density for resilience.

The Four Levels Explained

  • L (Low) — ~7% damage recovery
    Best for clean environments, maximum data capacity
  • M (Medium) — ~15% recovery
    Default choice for most uses
  • Q (Quartile) — ~25% recovery
    Great balance of size and durability
  • H (High) — ~30% recovery
    Ideal for logos, harsh conditions, or small print sizes

When to Use Each Level

Use H when adding a centered logo (it needs the extra redundancy). Use Q for outdoor posters or packaging. Use M for business cards and marketing materials. Use L only when space is extremely tight and conditions are perfect.

Pro Tip

Even with a logo, you rarely need more than Q if the logo is under 20% of the QR area and placed centrally.

FAQ

Does higher correction make the code bigger?

Yes — more dots are used for redundancy, increasing module count.

Can I scan a damaged H-level code with any phone?

Yes — all modern phones support all four levels natively.

Error correction isn’t a backup plan — it’s insurance for real-world use.