How big should a printed QR code be?

The one rule that covers almost everything: minimum code width = scanning distance ÷ 10. Scanned from 50cm, a code needs 5cm; from 3 metres on a poster, 30cm. Everything else is refinement.

Sizes that work, by use

• Business cards: 1.8–2.5cm — scanned in-hand, short URL or lean vCard only.
• Flyers and leaflets: 2–3cm, scanned at reading distance.
• Table talkers and menus: 2.5–4cm, arm's length.
• Posters: A4 → 3cm+; A1 street poster read from 2–3m → 20–30cm.
• Shop windows: pavement distance ~1.5m → 15cm minimum.
• Vehicle graphics: people scan parked vans from 2m+ → 20cm+, flat panel, not across ridges.
• Billboards: mostly theatre — at 20m the code must be 2m wide to scan, and nobody stops. Put the short URL beside it.

Density changes the maths

The rule assumes a typical code (~25×25 to 33×33 modules). Stuff a long URL or full vCard in and module count rises, so each square shrinks and you need more print size. Short links make physically smaller codes viable — another argument for lean data or an editable short-link code.

The quiet zone is not optional

The white border around the code — four modules wide — is how scanners find the edges. Designers trimming it "for tidiness" is the single most common print failure we see. Keep it.

Files: vector beats pixels

For anything print, export SVG (infinitely sharp at any size) or our 4096px PNG. Never screenshot a code and scale it up — blur at module edges is exactly what the scanner struggles with; the full failure list lives in QR code not scanning?. Always test-scan one printed proof at final size before the full run.