QR Code Size Calculator
Enter how far away people will be when they scan, and get the width your QR code should be printed at.
How big should the QR code be?
- Minimum width
- 10.0 cm (3.9 in)
- Safer width (dim light, long links)
- 15.0 cm (5.9 in)
| Where | Scan distance | Minimum width |
|---|---|---|
| Business card | 25.0 cm (9.8 in) | 2.5 cm (1.0 in) |
| Flyer or table card | 30.0 cm (11.8 in) | 3.0 cm (1.2 in) |
| Poster on a wall | 1.00 m (39.4 in) | 10.0 cm (3.9 in) |
| Shop window | 2.00 m (78.7 in) | 20.0 cm (7.9 in) |
| Large banner | 5.00 m (196.9 in) | 50.0 cm (19.7 in) |
The rule of thumb: distance divided by 10
A QR code scans reliably when its width is about one tenth of the distance it is scanned from. A code scanned from 1 metre away should be roughly 10 cm wide; from 2 metres, 20 cm. The calculator applies this rule and never goes below 2 cm.
Why 2 cm is the floor
Even at arm's length, a code much smaller than 2 cm (0.8 in) has modules so small that phone cameras struggle with focus and print resolution. For business cards, a clear 2 cm square on the back is the practical minimum.
Dense codes need more room
The more data a code holds, the more modules it has, and the smaller each one is at the same width. A long link, a vCard or a WiFi code with a long password makes a denser pattern, which is why the safer size adds 50%. Shorter links, or a dynamic QR code whose short link keeps the pattern simple, let you print smaller.
Print it and test it
Sizes are guidance, not a guarantee: paper, ink, glare and lighting all change what a phone can read. Print a proof at the final size and scan it from the real distance with two phones. The print size guide has more detail, and the QR code scanner is a quick way to check a proof.
Frequently asked questions
What is the smallest QR code that works?
About 2 cm (0.8 in) wide for close-range scanning. Smaller codes may scan on some phones in good light, but it is not reliable.
Does the code need a blank border?
Yes. Keep a clear margin of at least four modules around the code, and do not count it in the width above.
Do colors change the size I need?
Low contrast makes codes harder to read, so you may need more size or better contrast. Dark on light works best.