A QR on a name badge
A badge is read from half a metre, not from across the street. On qr-free.online a contact card or a short link is built with no account: the data stays in a file on your device.
What the badge should hand over
A name, a role and a work number in a contact card, or a short URL to a public page. Leave the home address and a personal messenger out of a code worn on the chest: strangers photograph badges.
Size on the card, and the clip
The square still has to read while the badge hangs on a lanyard. The clip, the ribbon and a fold in the card must not cover the matrix. Coloured card stock needs a white backing, or the modules sink into the colour.
One sample before the stack
Print a single badge and scan it on the lanyard, not flat on a desk. If the attendee list is still changing, a static file will not update itself. A profile link you can still edit is then built on QRcode Global; here you keep a one-off code for an event whose address stays put.