A QR code is a promise printed as a square: scan this and something specific happens. Codes get scanned when the promise is clear, the square is big enough, and the scan works on the first try. Most failed codes break one of those three rules, and none of the fixes are decorative.
Size and distance decide before design does
A phone camera needs the code to fill enough of the frame to lock on. The working rule is one-tenth: a code should be at least one-tenth as wide as the distance it will be scanned from. A business card scanned at arm's length needs roughly 2.5 centimetres; a poster read from three metres needs thirty. A conference banner with a card-sized code is decoration, not a doorway.
Contrast is the second mechanical rule. Dark modules on a light ground, quiet space around the square, and no recoloring that pushes the code toward its background. Brand-tinted codes can work; brand-tinted codes on brand-tinted backgrounds do not. Print a test, step back to the real distance, and scan it with a mid-range Android, not this year's flagship.
Say what happens after the scan
Nobody scans a naked square. The caption underneath is doing the persuasion, and it should name the outcome, not the mechanism. "Scan to save my contact" outperforms "Scan me". "Menu and today's specials" outperforms a bare code taped to a counter.
- Caption every code with the outcome
- One code, one destination — never a choice of squares
- Put it where hands are idle: badges, counters, packaging, table tents
- Skip it where nobody can stop: highway hoardings, moving slides
The destination is the actual product
The scan is three seconds; the page it opens is the experience. It must load fast on venue wifi, work in a portrait phone screen, and lead with the action the caption promised. If the caption said "save my contact", the save button comes first — not your life story. We covered that page's anatomy in how to make a digital business card people actually save.
For events specifically, the strongest setup is a code on your phone's lock screen or badge pointing at your contact card, because it works when your hands are full and your cards are forgotten. If a tap-to-share chip appeals to you, read the NFC guide first — QR and NFC end at the same page, and the page is what deserves the effort.
Point it at something you can edit
Printed codes outlive their content: menus change, roles change, campaigns end. Encode an address you control — your own page, not a file or a platform profile — so the printed square keeps working while the destination stays current. Our free QR code generator makes the square; making the destination worth scanning is the part that pays. When the code you are printing is your own introduction, start with the QR code business card — the page the scan opens matters more than the pattern itself.
