What the code contains
A VEVENT — the same block a calendar invitation email carries:
BEGIN:VEVENT
SUMMARY:Spring Open Day
DTSTART:20260912T100000
DTEND:20260912T160000
LOCATION:Hauptstraße 1, Berlin
END:VEVENTWhen a camera reads it, the phone recognises the format and opens its calendar with the fields already filled. The person taps save, or does not. Nothing is written without them.
Times are local, deliberately
Notice there is no time zone on those timestamps. That is not an omission — it is a floating local time, and for an event people physically attend it is the correct choice.
A doors-at-19:00 gig is at 19:00 for everyone standing outside the venue. If the code carried a zone, a phone still set to another country would helpfully shift the entry by an hour and the person would arrive late, having done nothing wrong. Floating time means the calendar shows what the poster said.
The one case where this is not what you want is a genuinely remote event across zones — a webinar. There, put the zone in the title: "Webinar (15:00 CET)".
Write the title for a stranger in three weeks
This is the mistake worth avoiding. The title makes sense to you now, in front of the poster. It has to make sense to someone scrolling their calendar on a Tuesday morning three weeks later, with no poster and no memory of scanning anything.
- "Open Day" — meaningless in a month.
- "Riverside School — Spring Open Day" — survives.
The same goes for the location: put the address people navigate to, not the room name.
Where it earns its place
- Posters and flyers — the moment someone decides to come is the moment to capture it.
- Tickets — printed or emailed, so the date survives the ticket being filed away.
- Conference programmes — a code per session, so people build their own schedule.
- Appointment cards — dentists, garages, anyone who hands over a date on card.
- Wedding and party invitations — where the save-the-date is the entire point.
In every one of those the alternative is the person typing a date into their phone, which is exactly the moment most of them decide to do it later and then do not.
Keep it short enough to print
Title, location and notes all sit inside the pattern. A long address plus a paragraph of detail can push the code past the point where it prints comfortably on a flyer. Keep the notes to one line, and if there is genuinely more to say, say it on a page and put the link in the notes.
Print the date as well
A poster whose date exists only inside a QR code is a poster that fails for everyone who does not scan it — which is most people walking past. The code is the shortcut for the ones who want it; the date in large type is what does the actual work.