How big a logo can you put on a QR code
5 min read
Putting a logo on a QR code works because of error correction. You are covering part of the message and relying on the redundancy to rebuild it. That means a logo is not decoration sitting on top of the code. It is damage you are choosing to inflict, and there is a budget for it.
Start with level H
If the design has a logo, set error correction to H before anything else. That gives you roughly 30% of the codewords back. Without it you are working from 15% or less, and the logo has to be small enough to look like an afterthought.
How large is safe
As a working rule, keep the logo under about 25% of the code's width, which is around 6% of its area. That sounds conservative against a 30% recovery figure, and it is, deliberately. The recovery budget also has to cover the things you did not plan: a fingerprint, a fold, glare from a phone flash, ink spread on cheap paper.
QR Best limits the logo to between 12% and 30% of the code width for this reason. Sitting at the top of that range is fine on a screen and risky in print.
Where it must go
The centre. Not a corner, not an edge, not tucked beside a finder pattern. The three large corner squares are how a scanner finds and orients the code, the dotted lines between them set the grid, and the bands beside them describe the format. None of that is protected by error correction, because the scanner reads it before decoding begins.
The centre of a QR code is ordinary data, spread through the code by an interleaving scheme that deliberately scatters related codewords. That is exactly the property that makes a centred hole recoverable.
Give the logo a plate
A logo dropped straight onto the modules blurs into them. Put a small solid margin of the background colour around it, so the scanner sees one clean covered region rather than a confusing mixture of logo and half-modules. QR Best does this automatically.
Contrast still rules everything
The modules must stay clearly darker than the background. A brand colour that looks confident on screen can be too light once it is ink on paper. If the logo is a pale colour, keep it inside its plate rather than letting it tint the surrounding modules.
The tool offers to match the code colour to the dominant colour of your logo. It is a good look, but check the result: matching a light brand colour lightens the whole code, and contrast is the single most common reason a stylish code fails.
Test it properly
Not on your own phone in good light at 15cm. Test on a cheap phone, at the distance and size the code will really be used, and with the printed piece rather than the screen. A code that scans on a laptop display and fails on a printed business card is the normal outcome of skipping that step.