QR code quality & error correction
The quality setting controls a QR code’s error correction — how much damage it can take and still scan. Here is what to choose.
In short
- Error correction (ECC) has four levels: L, M, Q and H
- Higher levels survive more damage, but pack the pattern denser
- For most uses, level M or Q is the sweet spot
- Add a logo? Use Q or H so the code still scans
What is error correction?
Every QR code stores redundant data using a technique called Reed–Solomon error correction. If part of the code is scratched, smudged or covered by a logo, the scanner can still rebuild the missing information — up to a point set by the ECC level.
Which level to choose
| Level | Recovers up to | Best for |
|---|---|---|
| L | ~7% | Clean digital screens only |
| M | ~15% | General print — the common default |
| Q | ~25% | Logos, or busy real-world surfaces |
| H | ~30% | Harsh conditions, large logo overlays |
Tips for a scannable print
- Keep strong contrast between the code and its background
- Leave a clear “quiet zone” (empty margin) around the code
- Print at a generous size — bigger is more forgiving
- Test the printed code before distributing it