QR code size calculator
How big should a QR code be?
Short answer: at least one tenth of the distance it is scanned from for a simple code, and bigger for a dense one, plus a white margin. Enter your distance for exact numbers.
By Wyatt, founder ·
Quick table
Minimum code width, with the white margin included in brackets
- Use (distance)
- Business card (25 cm)
- Short link (25 x 25 modules)
- 2.5 cm (3.3 cm)
- Typical web address (33 x 33 modules)
- 3.3 cm (4.1 cm)
- Long link, Wi-Fi, contact or a logo (45 x 45 modules)
- 4.5 cm (5.3 cm)
- Use (distance)
- Table tent (60 cm)
- Short link (25 x 25 modules)
- 6.0 cm (8.0 cm)
- Typical web address (33 x 33 modules)
- 8.0 cm (9.9 cm)
- Long link, Wi-Fi, contact or a logo (45 x 45 modules)
- 10.8 cm (12.8 cm)
- Use (distance)
- Flyer in hand or on a board (50 cm)
- Short link (25 x 25 modules)
- 5.0 cm (6.6 cm)
- Typical web address (33 x 33 modules)
- 6.6 cm (8.2 cm)
- Long link, Wi-Fi, contact or a logo (45 x 45 modules)
- 9.0 cm (10.6 cm)
- Use (distance)
- Poster on a wall (2 m)
- Short link (25 x 25 modules)
- 20.0 cm (26.4 cm)
- Typical web address (33 x 33 modules)
- 26.4 cm (32.8 cm)
- Long link, Wi-Fi, contact or a logo (45 x 45 modules)
- 36.0 cm (42.4 cm)
- Use (distance)
- Window or street sign (5 m)
- Short link (25 x 25 modules)
- 50.0 cm (66.0 cm)
- Typical web address (33 x 33 modules)
- 66.0 cm (82.0 cm)
- Long link, Wi-Fi, contact or a logo (45 x 45 modules)
- 90.0 cm (106.0 cm)
How the calculator works
- Start from the common 10:1 rule from QR code vendors: the code should be at least as wide as the scan distance divided by 10. It is guidance, not a standard.
- We read that rule against a simple code, 25 modules across (a short link). So one module, one square dot, must be at least the distance divided by 250.
- A denser code keeps the same dot size, so it grows: a 33-module code is 33 dots wide, a 45-module code 45.
- A dot is never smaller than 0.33 mm, about 4 printer dots at 300 dpi. On a thermal or 200 dpi printer, use 0.5 mm.
- Add the quiet zone, a blank margin 4 dots wide on every side. It is part of the code, so it is in the printed width.
Assumptions
- A phone camera in reasonable light, held roughly square to the code.
- Dark dots on a light background, with a contrast of at least 4.5 to 1.
- A flat, matte print. Glossy, curved or angled surfaces need one size up.
- Numbers are rounded up to the next whole millimetre.
What makes a code dense
- Longer content: a long web address, a Wi-Fi password, a full contact card.
- A logo: the strongest repair level (H) adds modules for the same content.
- Rough capacity at the medium repair level: 25 modules hold about 26 characters, 33 modules about 62 and 45 modules about 122.
- Shorten links where you can. The generator shows the code it will print, so you can count the modules.
Real examples
A business card read at about 25 cm with a short link: the code is 2.5 cm wide, 3.3 cm with its margin. A poster read from 2 m with a typical web address: 26.4 cm, or 32.8 cm with the margin.
The generator tests every design five ways before you download it, including a tiny version and a blurred one. Still print one copy at your size and scan it from where people will stand.
Make a code and check itQuestions
What is the minimum size for a QR code?
It depends on the scan distance. For a simple code read up close, like a business card at 25 cm, about 2.5 cm wide plus the white margin. Never print a dot smaller than 0.33 mm.
How big should a QR code be on a poster?
At 2 m with a typical web address, at least 26.4 cm wide. For a shop window or sign read from 5 m, use the calculator: it is several times bigger.
Does the white border count?
Yes. The quiet zone, 4 dots wide on every side, is part of the code. Phones need it to find the edges, so never crop it or print text into it.
Is bigger always better?
Up to a point. From very close, a code bigger than the camera's view cannot be read. Size it for where people stand.