Error correction (QR code)
Error correction is the redundancy built into a QR code, computed with the Reed-Solomon algorithm. It lets a phone read a code that is partly damaged, dirty or covered by a logo.
Updated September 24, 2026
The four levels
| Level | Recoverable share |
|---|---|
| L | about 7% |
| M | about 15% |
| Q | about 25% |
| H | about 30% |
Why it matters
The higher the level, the tougher the code, but the more modules it needs for the same data, so you print it a bit larger. Level H is required with a logo in the center, Q suits messy surfaces (placemats, outdoors), M is fine for everyday use. The QRTada designer picks for you: H with a logo, Q with fancy shapes or gradients, M otherwise. See QR code with logo.
Frequently asked questions
Which level should I use without a logo?
M works for most uses. Pick Q for surfaces exposed to stains or wear.
Does error correction slow scanning down?
No. It adds modules, so the code needs to be a bit bigger, but scanning stays instant.
Sources
Ready to print a QR code that never dies?
7 days for $0, card required, a reminder 2 days before the first charge, cancel in 2 clicks.