You build the link once and fill in the details with the merge tags of your email, automation or CMS tool, so every recipient gets an event for their own date, such as an appointment reminder.

Build a Smart Link

Start with https://my.calendarlink.com/link and add the event details as parameters:

Parameter	Value	Example
collection	The ID of the collection the event goes into. Required.	2b5ed630-a7a7-466f-92c5-90bc5d43999c
title	The event title	Dentist appointment
start	Start date and time	2026-10-20 10:00
end	End date and time	2026-10-20 11:00
duration	Length in minutes. Ignored when you set end.	60
timezone	The timezone of the start and end time	Europe/Amsterdam
location	An address or a meeting link	Main Street 1, Amsterdam
description	The event description	Bring your insurance card
redirect	Sends visitors straight to one calendar instead of the event page: google, apple, yahoo, office365, outlook, outlook_offline, teams or ical. Business plan only.	google

A complete link looks like this, with spaces written as %20:

https://my.calendarlink.com/link?collection=2b5ed630-a7a7-466f-92c5-90bc5d43999c&title=Dentist%20appointment&start=2026-10-20%2010:00&duration=60&timezone=Europe/Amsterdam

Opening the link takes the visitor to a normal event page, where they add the event to their calendar. With redirect, they go straight to that calendar.

Find the collection ID

Open the collection in your dashboard. The long code in the address bar after /collections/ is the collection ID. Use the collection ID, not the organization ID: a link with the organization ID shows a "not found" page. See API tokens and IDs.

Use merge tags

Replace fixed values with your tool's merge tags, for example the appointment date of each contact as start. Each recipient then gets their own event.

Events created by Smart Links

Opening the same link again shows the same event; it does not create a second one.
Smart Link events have only View public page and Analytics in their options menu. There is no Edit or Delete option for them. You find them at my.calendarlink.com/calendar/smart/ followed by the collection ID.

Tips

Build Smart Links in Google Sheets or Excel: put the details in columns and combine them into one link per row.
Seeing "Invalid date"? Check that start is filled in correctly and that the link has either end or duration.
A Smart Link is not stored in CalendarLink. Keep it in your own tool.