Why a code survives a logo
Every QR code includes error-correction data, extra information that lets a scanner rebuild parts of the pattern it cannot see. There are four levels. Level L can recover about 7% of the code, M about 15%, Q about 25% and H about 30%.
A logo works by covering part of the code and relying on that spare data to fill the gap. So the logo size and the error-correction level go together: a bigger logo needs a higher level, and a higher level makes the code denser.
Pick level H
When you add a logo in the logo generator, set the error-correction level to H. The generator suggests this as soon as a logo is present. Level M with a logo is the most common reason a branded code fails, because the logo alone can use up most of the spare data, leaving nothing for dirt, glare or a slightly blurred photo.
Keep the logo small
As a rule, the logo should cover well under a quarter of the code's area, and less is safer. The generator measures how much of the code your logo hides and shows a warning when it is too much for the chosen level. Take that warning seriously: the preview on your screen will often still scan when a printed copy in poor light will not.
Keep the logo in the centre. The three large squares in the corners, and the smaller one near the bottom right, are what the camera uses to find the code. Nothing should cover them.
Which logo file to upload
- A PNG or SVG with a transparent background works best. The generator clears a small area behind the logo so the dots do not run into it.
- Simple shapes read better than detailed ones. A logo mark or an initial usually looks better at this size than a full wordmark.
- Avoid very light logos. If the logo is pale, the cleared area behind it looks like a hole in the code. A dark or strongly coloured mark is easier to see.
The logo is processed on your device. It is not uploaded to us.
Do not stack risks
A logo is one risk. Light colours, a gradient, rounded dots and a very long link are others. Each one on its own is fine. Several together can tip a code over the edge. If you want a logo, keep the rest of the design plain: dark dots, a white background and a short link.
Test a printed copy
Download the code at the size you will print, print one, and scan it from the real distance with more than one phone. Then scan it again with the print tilted and in dimmer light. If it reads every time, print the batch. If it hesitates, shrink the logo or drop the gradient and try again.