QR codes for events, invitations and tickets
An event code has two jobs: before the day it saves the date and the address, and on the day it has to work in a crowd with no signal.
6 min read · Updated
The two jobs need different codes, and the usual mistake is to use the same content type for both. Below is which code to put on the invitation, the poster and the badge, and how to handle check-in at the door.
On the invitation: a calendar entry
The most useful thing an invitation code can do is put the event straight into the guest's calendar. Choose the Event content type in the generator, fill in the title, start, end and location, and scanning the code opens a prefilled “add to calendar” screen.
Two details matter. The first is the time zone. The code stores the time without one, so every guest's phone shows the event at the same clock hour in their own local time. If guests are in other zones, add the zone to the event title. Write the location as a full postal address, because the phone passes that text straight to its maps app, and “the usual place” will not find anything.
On a poster: a short link
Posters are scanned from a distance and often in a hurry, so the code needs large modules. A calendar entry is a lot of text and produces a dense grid. A short link to the event page gives a much coarser code that can be read from across a corridor. Put the calendar code on the page you link to, where people have time to use it.
By the distance ÷ 10 rule, an A2 poster read from 1.5–2 m needs a code about 15–20 cm wide. The size table covers other formats.
On a badge: a contact card for the wearer
Conference badges are where a contact card code earns its place: two people meet, one scans the other's badge, and the details are saved without anyone typing. Limit it to name, company, one email address and one phone number. A full vCard printed at 3 cm on a badge is dense enough to fail in a crowded hall.
Badges hang from lanyards, so they swing, twist and curl. Print the code with error correction Q or H, and place it low on the badge where a jacket lapel will not cover it.
At the door: assume there is no signal
Sooner or later every venue has this problem. Three hundred people arrive within ten minutes, all on the same mobile cell, and data slows to a crawl. If check-in depends on the guest's phone loading a page at that moment, the queue stops moving.
- Send tickets before the day and ask people to screenshot them or add them to a wallet app.
- Scan from the guest's screen with your device, using venue Wi-Fi or a local list, so check-in does not rely on their connection.
- Keep a printed guest list as a fallback for when phones or the network give out.
Ticket QR codes need a check-in system
A QR code says nothing about who is holding it. Anyone can photograph a ticket code and send the picture to a friend. If entry is paid or capacity is capped, each code must carry a unique identifier that your door system marks as used on the first scan. A static code that only says “admit one” works as an invitation but not as a ticket. That can be fine, as long as you know which of the two you are printing.
Where artistic codes belong
Invitations, save-the-dates and album-style posters are a good fit for halftone QR art, because the guest is holding the card still, in reasonable light, with time to spare. Use a plain code at the door, where scanning conditions are at their worst.