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Event details
Start
End
How it works: When a time zone is selected, the entered time is converted to UTC (the trailing Z form). No VTIMEZONE block is needed, so every calendar app reads the same instant. Lines longer than 75 octets are folded as RFC 5545 requires, and line breaks are written as CRLF.
ICS (iCalendar)
Bytes: 0 Lines: 0
Related tools: Calendar Event QR Code Generator Date Difference Calculator Time Zone Converter Japanese Address Generator

Frequently asked questions

What is an ICS file used for?

It is the standard format for importing an event into a calendar application. Google Calendar, Apple Calendar and Outlook all read it. It is commonly attached to email or offered for download on a website so people can add an event to their own calendar.

How are time zones handled?

The time you enter is read as a time in the zone you selected and written out in UTC (the trailing Z form). No VTIMEZONE block is required, so every application reads the same instant. If you do not want any offset applied, choose the no time zone option and the event is written as a floating time read as local time on the device that opens it.

Why is the end date of an all-day event one day later?

RFC 5545 defines DTEND of an all-day event as the day after the last day. For an all-day event on 26 September, DTSTART is 20260926 and DTEND is 20260927. This tool adds that day for you.

Can I use a long title or description?

Yes. RFC 5545 limits a line to 75 octets, so longer lines are folded onto continuation lines that begin with a space. Multi-byte characters are measured in UTF-8 bytes so a character is never split in the middle.

Is my input sent to a server?

No. Generation and download run entirely in your browser. The event details are never sent to or stored on a server.

How to use

  1. Enter a title — Type the event name shown in the calendar. Without it no ICS is produced.
  2. Set the date and time — Enter the start and end date and time. Tick the all-day option to hide the time fields.
  3. Choose a time zone — Select the zone the entered time belongs to. Japan Standard Time is the default.
  4. Add recurrence and a reminder — Optionally choose a repeat rule (daily, weekly, monthly, yearly) with a count, and how many minutes before the start to be reminded.
  5. Download the file — The generated ICS appears on the right. Use the download button to save it as a .ics file and open it in your calendar app.