Logos on QR codes, what size?

Question

Design

When generating QR codes, you can add a logo in the middle of the code
Question: How many pixels to make a logo so that the code is still readable?

Answer 1

Best of all, none. This is once again marketing crap wins over common sense.
The QR is designed so that it contains redundant information, this is done specifically for reliable reading, for example, when dirt has got in, or a corner of the code has come off, or the camera cannot focus properly, etc.
The larger the piece you cover with the logo, the less redundant information will remain. Those. your QR will still be read in perfectconditions, but a little bit of a defect or interference - is not considered. But people tried, invented how to encode with redundancy. If they knew that marketers would flush their difficult intellectual work down the toilet like this, they would have left an empty space in the middle in advance - go ahead, guys, sculpt logos here.

Answer 2

Any. Its size depends on how much information you want to record.