Adding a logo to a QR code: error correction explained
A QR code can still be read when part of it is covered or damaged. That's what makes logos possible. Understanding how it works helps you add one without breaking the code.
Error correction levels
| Level | Can recover | Use it for |
|---|---|---|
| L | About 7% | Clean screens and documents with lots of data |
| M | About 15% | Everyday print |
| Q | About 25% | Print that may get scuffed, small logos |
| H | About 30% | Logos, rough surfaces, outdoor signs |
Higher levels store extra recovery data, so the pattern gets denser. That's the trade-off: more protection, smaller modules.
How big can a logo be?
With level H, up to about 30% of the code can be unreadable, but that budget also has to cover dirt, glare and printing flaws. In practice keep logos to about a third of the code's width (around 10% of its area) and centered. Our generator switches to H automatically when you add a logo and limits the logo size.
Never cover these parts
- The three large corner squares. Scanners use them to find the code.
- The quiet zone around the code.
- The small alignment square near the bottom right on larger codes.
Tips for logos that scan
- Use a simple, high-contrast logo. Thin text inside a logo won't be readable at small sizes anyway.
- Turn on 'Clear the code behind the logo' so modules don't peek out around it.
- Shorter content means bigger modules and more room for a logo. A dynamic code helps.
- Always check the scan result before you download. We test every design with a real decoder.