QR code glossary.
Sixteen terms you meet when printing, tracking and troubleshooting QR codes, each with a diagram of the part it describes.
All terms
- Alignment patternA smaller square near the bottom-right that corrects for perspective and curved surfaces.
- Dynamic QR codeA QR code that encodes a short link, so the destination can be changed after printing.
- Error correction (ECC)Redundant data that lets a QR code be read when part of it is damaged or covered.
- Finder patternThe three large squares in the corners that tell a scanner where the code is and which way up.
- GS1 Digital LinkA web URI format that carries GS1 identifiers like a GTIN, readable by both tills and phones.
- GTINGlobal Trade Item Number — the 8 to 14 digit product number behind a barcode.
- Logo in a QR codeA mark placed over the centre of a code, relying on error correction to stay readable.
- ModuleOne square of a QR code — the smallest unit, dark or light.
- Quiet zoneThe empty margin around a QR code, four modules wide, that scanners use to find its edges.
- RedirectThe server response that sends a scanner from the short link to the current destination.
- Short linkA brief URL that redirects to a longer destination.
- Static QR codeA QR code whose content is fixed in the modules at the moment it is generated.
- Timing patternAlternating dark and light modules between the finder patterns that set the grid spacing.
- UTM parametersTags added to a URL, like utm_source=poster, that analytics tools use to attribute visits.
- VersionThe size of a QR code grid, from version 1 (21 × 21) to version 40 (177 × 177).
- X-dimensionThe printed width of a single module, in millimetres.