QR code error correction, explained with a live demo
What the L, M, Q and H error-correction levels really mean: drag the slider to damage a live QR code and watch when each level stops scanning.
Pick an error-correction level. Higher levels add more redundancy and more modules.
Drag the damage slider to cover part of the code.
The verdict updates live as the decoder loses and regains the code.
Questions
What do the QR error correction levels mean?+
L recovers about 7% of damaged data, M 15%, Q 25% and H 30%. Higher levels cost more modules, so the code gets denser for the same content.
Which level should I use?+
M for most links. Q or H when a logo will cover the centre or the print will live outdoors. L only when the code must be as small as possible and stays clean.
Does error correction let me put a logo in the middle?+
Up to a point. Covering under 20% of the area with level H usually works. Covering a finder pattern in a corner never does, at any level.
How does AriaQR fit a whole picture in?+
It does not rely on error correction to hide damage. The image is placed in the free bits of the code so the data is intact, then every code is verified on real decoders.
More free tools
The next step
Make the code the artwork.
These tools make and check classic codes. AriaQR turns your photo, logo or illustration into the code itself, verified on real decoders before you download, with a link you can edit and track.
