A QR Code with a logo in the middle is recognised instantly, looks more trustworthy and ties in with your brand. But there is a risk: the logo covers part of the pattern, and if it covers too much the code stops scanning. Here is how it works and how to add one safely.
Why a QR Code can hold a logo
QR Codes contain error correction: part of the data is repeated so that the code can be read even when it is slightly damaged or covered. At the highest level, up to about 30% of the pattern can be lost. The logo uses exactly this margin: it covers some modules and the phone rebuilds the missing ones.
On DenQr, when you add a logo, error correction is automatically set to high and the logo takes up about a fifth of the code’s width: enough to be seen, not so much that it breaks scanning.
How to add the logo, step by step
- Open the QR Code generator and choose the type you need.
- In the customisation section open the Logo tab and upload the file.
- Check the preview: the logo stays in the middle and the three squares in the corners must be clearly visible.
- Choose colors with good contrast: dark code, light background.
- Download the code and test it with at least two phones before printing.
Which logo works best
- Simple and compact: the symbol or initial, not the full logo with a long wordmark.
- Square or round: very wide shapes cover more modules for the same height.
- With a solid background (white or your brand color) and a little padding around it: it stands out better from the pattern.
- A good-quality file: PNG with a transparent background or SVG, not a grainy photo.
Rules to avoid breaking the code
- Do not cover the “eyes”: the three squares in the corners are what the phone uses to find the code.
- Do not enlarge the logo: on DenQr the size is already fixed; if you rework the code in a graphics program, do not make it bigger, as it is the main reason a code stops scanning.
- Prefer a dynamic code: it contains a short address, so the pattern has fewer modules and holds a logo better. A static code with a long address is denser and more fragile. See static vs dynamic.
- Print it large enough: the logo takes away some of the scanning margin, so do not go below 2.5-3 cm.
- Contrast first: even the nicest logo will not save a light-grey code on white.
How to tell if it is too much
If the phone takes more than a second to recognise it, or only some phones read it, the code is at its limit: simplify the logo, increase the contrast or the print size. When you save, DenQr discards designs that would make the code unreadable; testing with different phones is still the check that counts.
For all the other printing rules see the guide How to print a QR Code that always scans.