Guide
QR Code Error Correction: L, M, Q, and H Explained
The error correction levels L, M, Q, and H define how much redundancy a QR code contains. A higher level can help when damage is expected, but it doesn't automatically make the code better.
The Four Levels
L offers the least redundancy, H the most. M and Q sit in between. The actual amount of damage that can be corrected also depends on the QR version, print quality, and type of damage.
Capacity vs. Redundancy
More redundancy requires additional modules. With the same content, this can make the pattern denser. The right setting depends on output, data amount, and expected wear.
Logos and Hidden Modules
A logo covers part of the pattern. Higher error correction can make sense for this, but it doesn't replace checking size and contrast.
The logo should stay centered, high-contrast, and small enough. QRWerk's visual quality check warns about critical settings.
Practical Recommendation
Start with a suitable medium setting and test the finished code in the intended medium. Don't reflexively choose H if it results in an unnecessarily dense code.
Editorial basis
Publisher: QRWerk. The technical statements refer to the current QRWerk functionality and the related payload, browser and export tests. A publication or revision date will be added only after a separate content review.