QR code with logo
A QR code with your symbol in the middle looks like yours, but a logo hides part of the code and can make it unreadable. Opo Codes sizes the logo by actually decoding the code, so it grows only as large as still scans, and runs the scan check before you download. It all runs in your browser.
Open the generatorFree. Runs in your browser.
How to do it
- Open the generator and choose what the code holds, such as a link.
- Open the Logo tab and drop in your symbol as a PNG, JPG or SVG file.
- Wait while the generator fits the symbol by decoding, and read the line that says how much of the code is cleared.
- Check for the VERIFIED stamp, then download. A VOID stamp with the reason Logo too large means the symbol has to be smaller or simpler.
How the fitting works
Error correction is forced to H, the highest of the four levels L, M, Q and H, because the logo removes modules. The symbol clears the modules along its own outline plus a margin of 0.7 module around it, never the three big corner squares or other fixed patterns. The symbol may clear at most a quarter of all modules and may be no wider than half the code.
The size is not a fixed percentage. The generator tries sizes between 1 module and 45 percent of the code height, keeps the largest one that still decodes both at print size and at a small size, then steps back to 85 percent of it. Real phone cameras are worse than a clean render, so the 15 percent is room to spare.
Preparing the symbol
Use a symbol, not a wordmark with small text. White margins are trimmed, and a plain near-white background is removed from the edge inward, so white inside the symbol stays. A symbol must be no wider than 3 to 1 and no taller than 3 to 1. Worked example: a banner 400 pixels wide and 100 high is 4 to 1 and is refused with the message to crop it. Cropped to 300 by 100 it is 3 to 1 and is accepted.
If the symbol is light on white, its contrast is under 3 to 1, so it is given a dark plate behind it. The generator tells you when that happens.
Free preview, and what to check
Your own symbol in the code is listed as a Pro feature on the pricing page. While Opo Codes is in its free preview the Logo tab is open to everyone.
The scan check is a software test. Our plan also lists a test on real phones, including an older Android, as still to be recorded, so scan your printed code on a few phones before a large run.
Questions
Why does the logo make the code denser?
Level H adds extra correction data so the code can survive the missing modules. That makes the code larger in modules, so print it a little bigger.
Which files can I use?
PNG, JPG or SVG. Anything else is refused with a message to use one of those three.
What does VOID with Logo too large mean?
After placing the logo, the code no longer decodes. Use a simpler or smaller symbol, or a shorter link, which gives a less dense code with more room.
Can I add text as a logo?
The tool is for symbols. A frame such as Scan me adds words around the code without covering its modules.