Add-to-Google-Calendar links

What the link actually is

Google accepts an event as a URL: calendar.google.com/calendar/render with the title, times, location, and description as query parameters. Nothing is stored on Google’s side until the person clicks save, so the link works for anyone — they do not need to be the account that made it, and you do not need an account at all to build one.

The same event produces links for Outlook.com, Office 365, and Yahoo at the same time, and downloads as an .ics file for Apple Calendar, Thunderbird, and everything else. Pick whichever your audience uses; the event is identical in all of them.

Where a link beats a file

A link is better in an email, a newsletter, or a web page: one tap, no download, nothing to open. A file is better when the recipient’s calendar is not one of the four web services above, when the event must survive being forwarded, or when you want it saved somewhere permanent. Most invitations want both — a link for convenience and a file for the people whose calendar you cannot guess.

Questions

Does the person clicking the link need a Google account?

They need one to save the event, since it lands in their own calendar. The link itself is public and works for anyone; Google prompts them to sign in if they are not already.

Can I put the link on a button on my site?

Yes — it is an ordinary URL, so any anchor or button works. If you would rather let visitors build their own event, the whole builder embeds with one script tag.

Will guests I add get an invitation?

Not from the link. Guest addresses travel in the .ics file, and it is the calendar or mail client that sends invitations when the organiser saves the event. A prefilled Google link fills the fields; it does not send mail on your behalf.

What happens to the time zone in a link?

Google is told the zone explicitly when you pick one, so everyone sees the same instant. With no zone chosen, the event uses the clock time you typed, interpreted in whatever zone the person saving it lives in.