Surface guide
QR codes on mugs and drinkware
A mug is a cylinder about 8 cm across, so a QR code has roughly 8 cm of usable arc before curvature defeats the decoder. Keep the code to 2.5–3.5 cm and centre it on the flattest part facing the viewer.
| Typical scan distance | 20–30 cm |
|---|---|
| Minimum code width | 2.5–3.5 cm |
| Error correction | Q |
The curvature limit
Keep the code within about one third of the circumference. On a standard 8 cm-diameter mug that is roughly 8 cm of arc, and a 3 cm code sits comfortably inside it. Beyond a third, the edge modules foreshorten past what alignment patterns can correct.
Use at least a version-2 code (25 × 25) so alignment patterns exist at all — version 1 has none, and a version-1 code on a curve is unreliable.
Print method
- Sublimation on a coated mug: sharp, dishwasher-durable, the default choice.
- Ceramic decal + kiln firing: the most durable, best for anything long-lived.
- Direct UV print: sharp but the ink sits proud and wears at the edges.
Dishwasher survival
Sublimation and fired decals survive hundreds of cycles. UV-printed and vinyl-applied codes degrade in tens. If the mug is for a café rather than a shelf, insist on sublimation or fired decal.
Placement
Opposite the handle for a right-handed grip, or on both sides. A code under the handle is unscannable by half your users.