How Big Should a Printed QR Code Be?

14 August 2026 · Free QR Pro

There is a real answer to this question, and it is arithmetic rather than taste: one tenth of the distance the code will be scanned from. Everything else in this guide is that rule applied to real objects.

The one-tenth rule

Scanner manufacturers quote the same working ratio: a code is comfortable to read when its printed width is at least one tenth of the scanning distance. Read at arm’s length — say 40 cm — a code wants 4 cm. Read across a room at 3 m, it wants 30 cm. Round up, always: phone cameras vary wildly, older ones focus slowly, and real lighting is worse than your desk.

Worked examples

Business card — scanned in hand at 25–30 cm: 2.5–3 cm. That fits, which is why card codes work at all.

Table tent or counter card — 30–50 cm: 3–5 cm, standing upright so it faces the camera rather than the ceiling lights.

Wall poster — first scan attempt from 1–2 m: 10–20 cm of code, not the 4 cm square left over after the designer finished.

Vehicle or shopfront — 3 m and up: 30 cm minimum, and question whether a URL in large type would serve better.

Why data density moves the answer

The rule assumes a typical short URL. Every extra character adds modules to the grid, and at a fixed print size more modules means smaller modules — which is the same as printing smaller. A 250-character link at 3 cm is far harder to read than a 30-character link at the same size. Shorten what you encode before you enlarge what you print; the bulk generator’s density meter exists precisely to flag the worst row in a batch before anything is printed.

Sizes are in millimetres for a reason

Screens lie about size, so the print-sheet mode on the batch pages lays codes out in real millimetres on A4 or US Letter, with cut marks. One more print rule that outranks all of this: a printed code can never be edited afterwards, so make sure the address it carries is one you own — the static-versus-dynamic choice matters most at the moment of printing.