A QR code that's too small or too low-resolution simply won't scan, wasting the materials it's printed on. Getting size and resolution right for each medium, from a business card to a billboard, is what guarantees a reliable scan every time. Here's a practical guide.
The Distance Rule
The core principle is that scanning distance dictates size. A rough guideline is that a code's width should be about a tenth of the distance it will be scanned from. A code scanned at arm's length can be small; one scanned across a room or from a road must be far larger.
Sizes by Medium
On a business card, aim for at least three quarters of an inch square. On flyers and packaging, around an inch or more. On posters scanned from a few feet, several inches. On billboards or signage scanned from far away, the code must be scaled up dramatically to stay readable.
Resolution and File Format
For print, resolution matters as much as size. Export a high-resolution PNG sized for the final print, or use a vector format for large formats so the code stays crisp at any scale. A low-resolution image enlarged for print turns blurry and fails.
Always Keep the Quiet Zone
Whatever the size, preserve the quiet zone, the blank margin around the code, since scanners need it to detect the pattern. Crowding the code against text or edges is a frequent cause of failure even when the size is correct.
FAQ
Common questions are answered in the FAQ section below.