QR code size calculator: how big should the code be?
Enter the distance people will scan from and what the code contains, and get a minimum print size and margin.
Calculate a size
Runs in your browserTurn any long URL into a short, trackable link.
Once the destination checks out, shorten it with click analytics by source, location and device, all in one dashboard.
Why size depends on distance and data.
A phone has to resolve each square of the code, so what matters is how big the squares look from where it is.
A widely used rule of thumb is a 10 to 1 ratio: a code should be about one tenth of the distance it is scanned from. A poster read from three metres needs a code around 30 cm wide, and a business card held at arm's length is fine with 2 cm.
The amount of data matters too. A longer address needs more squares, so each square becomes smaller at the same overall size. A short link gives a coarser pattern that stays readable when small.
The code also needs a quiet zone: a clear margin of at least four squares on every side, with nothing printed inside it.
Common questions
What is the smallest QR code that scans reliably? +
About 2 × 2 cm for a short link on a good print, scanned from close up. Below that, many phones struggle.
Does the surface matter? +
Yes. Glossy or curved surfaces cause reflections and distortion, so add margin to the size on bottles, windows and screens.
What about contrast? +
Dark code on a light background is the safest. Low contrast or inverted codes fail on some scanners.
How can I make a code easier to scan? +
Encode less. A short link behind the code gives a simpler pattern than a long URL.