It is a plain-text calendar file in the iCalendar format, defined by RFC 5545. It carries one or more events with their times, descriptions, attendees and reminders, and every mainstream calendar application can open one.

How do I add an ICS file to Google Calendar or Outlook?

Open the downloaded file — both applications register the .ics type and offer to add the event. For a public event page, attach it to an email or link to it, which is how conference and webinar invites are usually distributed.

Why do ICS lines wrap with a leading space?

The format limits a content line to 75 octets. Longer values are folded onto continuation lines that begin with a single space, and the parser strips that space when reading the value back.

What is the difference between a floating time and a time zone?

A floating time has no zone attached and displays at the same clock time everywhere — right for something like a daily reminder. A zoned time is anchored to a place, so it converts correctly for people elsewhere and survives daylight saving changes.

Can one ICS file contain a repeating event?

Yes. An RRULE line describes the repeat — FREQ=WEEKLY;COUNT=8 for eight weekly occurrences — and the calendar expands it locally rather than storing eight separate events.

ICS Calendar File Generator

Build a valid .ics invite with reminders, repeats, attendees and a proper time zone — correctly escaped and folded.

The ICS Calendar File Generator runs entirely in your browser. Event details and attendee addresses are never uploaded.

Open the World Clock & Time Zone Converter

关于 ICS Calendar File Generator

An .ics file is the universal calendar invite: attach it to an email, put it behind a download link on an event page, or open it yourself, and every calendar application understands it. The details that decide whether it opens cleanly are unglamorous — commas and semicolons carry meaning and have to be escaped, lines must be folded at 75 octets with a leading space on the continuation, and every timestamp has to declare whether it is UTC, floating, or tied to a named zone. All three are handled here. The generator also validates the fields clients silently refuse without, and produces a matching Google Calendar link for people who would rather click than download.

功能特性

Timed or all-day events, with the exclusive end date all-day events require
Named IANA time zone, or a deliberate floating time
Daily, weekly, monthly or yearly repeats with an optional count
Display reminder from five minutes to a day before
Organiser and any number of attendees with RSVP flags
Correct escaping of commas, semicolons and newlines
Line folding at 75 octets that never splits a character
A matching Google Calendar add-event link
The file is generated in your browser

如何使用 ICS Calendar File Generator

Enter the title, time and location of the event
Pick the time zone, or leave it floating
Add a reminder, a repeat rule and any attendees
Download the .ics file or copy its contents

示例

输入

Quarterly review · 1 Sep 2026, 14:30-15:30 · Europe/London · 15 min reminder

输出

DTSTART;TZID=Europe/London:20260901T143000
DTEND;TZID=Europe/London:20260901T153000
BEGIN:VALARM
TRIGGER:-PT15M

A named zone keeps the event at the right local time when the clocks change.

常见错误与故障排除

The all-day event shows one day short in the calendar. — An all-day DTEND is exclusive: a single day on 1 September needs a DTEND of 2 September. The generator adds the extra day for you, so enter the last day the event actually runs.
The event appears at the wrong time for people in other countries. — A floating time shows at the same clock time wherever it is opened. Set a named time zone so the event converts properly for everyone.
Re-importing the file created a duplicate instead of updating. — The UID changed between exports. Keep the same UID and calendars treat the second file as an update to the existing entry.

常见问题

What is an ICS file?: It is a plain-text calendar file in the iCalendar format, defined by RFC 5545. It carries one or more events with their times, descriptions, attendees and reminders, and every mainstream calendar application can open one.
How do I add an ICS file to Google Calendar or Outlook?: Open the downloaded file — both applications register the .ics type and offer to add the event. For a public event page, attach it to an email or link to it, which is how conference and webinar invites are usually distributed.
Why do ICS lines wrap with a leading space?: The format limits a content line to 75 octets. Longer values are folded onto continuation lines that begin with a single space, and the parser strips that space when reading the value back.
What is the difference between a floating time and a time zone?: A floating time has no zone attached and displays at the same clock time everywhere — right for something like a daily reminder. A zoned time is anchored to a place, so it converts correctly for people elsewhere and survives daylight saving changes.
Can one ICS file contain a repeating event?: Yes. An RRULE line describes the repeat — FREQ=WEEKLY;COUNT=8 for eight weekly occurrences — and the calendar expands it locally rather than storing eight separate events.