Print a multi-size QR test sheet before the poster run
Screen zoom lies. A sheet of real sizes on the wall you will use tells you which footprint still scans.
OpenNews
Short notes on quiet zone, contrast, and print size — each one links to a free proofing tool.
Quiet zone fails on dark posters: leave a clear margin
A QR needs empty space around it. Busy backgrounds and tight crops are a common print reject.
OpenWhy a 2 cm QR still fails: contrast and viewing distance
Small codes need strong contrast and enough printed size for the distance people will stand.
OpenUpdated 12 November 2026.