QR codes on cylindrical packaging: cans, bottles and jars

The rule, applied to real containers

The curved surfaces page derives the limit: code width ≤ circumference ÷ 6, so the symbol spans no more than 60° of arc. Here it is for the packaging you are actually holding:

Container	Diameter	Circumference	Max code width
Cosmetic tube	30 mm	9.4 cm	1.6 cm: marginal, see below
Slim 330 ml can	53 mm	16.6 cm	2.8 cm
500 ml PET bottle (body)	65 mm	20.4 cm	3.4 cm
Standard 330 ml can	66 mm	20.7 cm	3.4 cm
Wine bottle (body)	75 mm	23.6 cm	3.9 cm
Jam jar	80 mm	25.1 cm	4.2 cm
1 l paint tin	110 mm	34.6 cm	5.8 cm

Two sanity checks before you commit a size. First, the ten-to-one distance rule: a 2.8 cm code supports scanning from about 28 cm: fine in the hand, inadequate on a shelf. Second, the module floor: divide the width by the module count and keep each module at or above the minimum for your print process: the size calculator does both checks from the payload.

Worked example: a canned drink

A campaign URL of 38 characters at error correction M encodes as version 3: 29 modules, 37 module-widths including the quiet zone. On a slim can, 28 mm ÷ 29 ≈ 0.97 mm per module: comfortable for any label press. Add 60 characters of tracking parameters and the code becomes version 6 (41 modules): 28 mm ÷ 41 ≈ 0.68 mm, still printable, but the margin has halved for no benefit the user sees. Short payloads are the cheapest engineering on a cylinder.

Wrap direction and placement

• Only one dimension of the square wraps the curve; the other lies along the can's flat axis. Place the code level and centred on the primary display panel, so the customer faces it square-on without rotating the container.
• Keep the code away from the label seam and at least a quiet zone's distance from embossing, ribs, shoulder curves and the neck taper, where the surface stops being a simple cylinder.
• On jars, the vertical wall between the shoulder and the base label area is the flattest band: avoid the curved shoulder entirely.

Shrink sleeves distort artwork on purpose

Full-body shrink sleeves are printed flat and then shrunk onto a contoured container, so sleeve prepress pre-distorts the artwork to compensate. A QR code that gets pre-distorted like the rest of the design can come out with unequal module widths. Tell the converter the code must survive as a square grid: keep it in the straight-walled zone with the least shrink, and approve a scanned sample from the actual shrunk sleeve, not the flat proof. The same applies to conical cups, where every horizontal line is an arc: treat cones as hostile and prefer the flattest band.

When the cylinder is too thin

At a 1.6 cm cap, a cosmetic tube can just about carry a version 1–2 code with a short URL. Anything denser belongs on the cap, the crimped end, the folding carton or a swing tag. That decision tree, plus rMQR's honest limitations, is covered under curved surfaces. For the broader packaging workflow (materials, finishes, proofing) see QR codes on product packaging and the packaging size guide.

FAQ

How big can a QR code be on a can?

Circumference divided by six. A standard 66 mm-diameter can has a 20.7 cm circumference, so keep the code at 3.4 cm or less. A slim 53 mm can caps it at about 2.8 cm.

Why does my QR code fail on a bottle but scan when the label is flat?

The wrap tilts the outer columns of modules away from the camera. If the code is wider than a sixth of the circumference, that foreshortening exceeds what the decoder's perspective correction can recover.

Do shrink sleeves affect QR codes?

Yes. Sleeves are pre-distorted in prepress to compensate for shrinking onto the container's contours, and that distortion can warp the code's grid. Keep the code in the straightest zone and approve a scanned sample of the shrunk sleeve.

Where should a QR code go on a jar?

On the vertical wall between shoulder and base, centred on the display face, clear of the seam and the curved shoulder. Keep the full quiet zone inside the flat band.