Find the smallest QR code that still scans reliably. Enter how far away people will scan it and what it contains; the calculator works out the QR version, the size of each module and the minimum print size.
Recommended size
Estimates assume a typical phone camera, good light and a flat code. Always test-scan a printed proof at the real distance.
Three things decide how big a QR code must be: how far away it is scanned, how much it contains, and how well it is printed.
Distance. Phones read a code comfortably when the code is at least about one tenth of the scanning distance. A poster read from 3 m needs a code around 30 cm wide.
Content. The calculator finds the smallest QR version that fits your content at the chosen error-correction level. Each version adds 4 modules per side, from 21 × 21 up to 177 × 177.
Module size. The printed size divided by the number of modules (plus the 4-module quiet zone on each side) gives the size of one square. Below about 0.4 mm close up, cameras start to struggle; each module should also cover at least 3 to 4 printer dots.
Quick reference
Business card or label, scanned from 10–30 cm: 2–3 cm.
Flyer or menu on a table, 30–60 cm: 3–6 cm.
Poster on a wall, 1–2 m: 10–20 cm.
Window or banner, 5 m: about 50 cm.
Keeping the content short is the easiest way to allow a smaller code. Read the full QR code size guide for print.
Frequently asked questions
How big should a QR code be?
At least 2 × 2 cm (about 0.8 × 0.8 in) for close-up scanning, and roughly one tenth of the scanning distance for anything further away: 10 cm wide for 1 m, 50 cm for 5 m. More content or a higher error-correction level needs more space.
What is the 10:1 rule for QR codes?
A common rule of thumb: the scanning distance should be no more than about 10 times the width of the code. It assumes a typical phone camera and good light; dense codes need a more generous ratio.
Why does more content make the QR code bigger?
More data needs a higher QR version with more modules. At the same print size each module gets smaller and harder for a camera to resolve. Shorter links (for example a dynamic QR code) keep the code simple.
What is a QR module?
One black or white square of the code. A version 1 code is 21 × 21 modules and every version adds 4 modules per side, up to 177 × 177 for version 40.
Does a logo change the size I need?
A logo usually requires error correction H, which uses a higher version for the same content. Size the code with level H selected when you plan to add a logo.