Calendar Invite

What it's for

Read a calendar invitation or event file (.ics) without adding it to your calendar, and make one for others to add to theirs. Invitations hide their details in a text format, with times in the sender’s time zone and repeats written as rules.

• When you’re unsure what an invitation is: see when it really is in your time, who’s invited and how they’ve replied, how it repeats, and whether it’s an update or a cancellation.
• When you’re organising something: make an .ics file to attach to an email or put on a web page, which any calendar can add.

How to use it

To read a file, choose it, drop it on the page, or paste its text (an email’s attachment, or the text of a text/calendar part). Each event shows its date and time in its own time zone and, when that’s different, in yours; Outlook’s Windows zone names are understood. Then the organiser, attendees and their replies, the repeat rule in words with the next dates, reminders, the online meeting link (Teams, Zoom, Meet or Webex), and anything wrong, such as a missing UID or an end before the start.

To make a file, fill in the event. Save .ics downloads it, named after the title. It uses the time zone you choose (yours to start with), so people elsewhere see it at their own time.

Example

Paste this:

BEGIN:VCALENDAR
METHOD:REQUEST
BEGIN:VEVENT
UID:42@example.com
DTSTAMP:20261001T080000Z
SUMMARY:Quarterly review
ORGANIZER;CN=Alice:mailto:alice@example.com
ATTENDEE;CN=Bob;PARTSTAT=ACCEPTED:mailto:bob@example.com
DTSTART;TZID=Eastern Standard Time:20261103T100000
DTEND;TZID=Eastern Standard Time:20261103T110000
RRULE:FREQ=MONTHLY;BYDAY=1TU;COUNT=3
END:VEVENT
END:VCALENDAR

It shows Tuesday, 3 November 2026 at 10:00 to 11:00 (America/New_York), and in the UK Your time: Tuesday, 3 November 2026 at 15:00. Bob has accepted, it repeats Every month on the first Tuesday, 3 times, and the next dates are 3 November, 1 December and 5 January.

Good to know

Reading a file doesn’t reply to it or add it to a calendar. Repeats are worked out for daily, weekly, monthly and yearly rules (hourly ones and some rare options aren’t). A time zone the browser doesn’t know is read from the file’s own description of it. Made files are plain events to add, not invitations with attendees.