Glossary
Quiet zone
The quiet zone is the blank margin around a QR code. The specification requires at least four modules of clear space on every side, and codes fail more often from a missing quiet zone than from almost any other design error.
Four modules, not four millimetres
The requirement scales with the code. Four modules on a code with 0.5 mm modules is a 2 mm margin; on a large poster code with 3 mm modules it is a 12 mm margin. Designers who set a fixed pixel padding get this wrong in one direction or the other.
Micro QR codes need only two modules.
What counts as violating it
- Text or a logo placed inside the margin.
- The code butting against a coloured panel or a photograph.
- A border or frame drawn tight to the pattern.
- The code sitting at the very edge of a label, where the trim cuts into it.
A frame is fine — but the frame must sit outside the four-module margin, not on it. This is why UseQR keeps the quiet zone as an explicit parameter rather than treating it as decoration.
Related
- Module — A module is one square cell of a QR code — the smallest unit of the pattern. Codes are measured in modules, not pixels or millimetres, because the module…
- Finder pattern — The three large concentric squares in the corners of a QR code are finder patterns. A scanner locates them first to work out where the code is, how big it…