# What Is an ICS File? How to Open One in Any Calendar

URL: https://gocutline.com/how-to/what-is-an-ics-file/

An .ics file is a plain text file that holds calendar events in the iCalendar format, a shared standard that Google Calendar, Outlook, Apple Calendar and almost every other calendar app can read. Open it and your calendar app offers to add the events.

## Step by step
1. On a computer, double-click the file: your default calendar app offers to add it.
2. For Google Calendar, use [Import & export](https://gocutline.com/how-to/import-ics-google-calendar/).
3. For Outlook, use [Upload from file](https://gocutline.com/how-to/import-ics-outlook/).
4. On an iPhone, tap the file and then **Add All**.

## Good to know
- **Importing** copies the events once. **Subscribing** to a link keeps following changes.
- An .ics file can hold one event or thousands of them.
- The format is plain text, so you can open one in a text editor to see what is in it.
- Want one to try? Each country in our [public holidays list](https://gocutline.com/holidays/) has a file.

## Source
This guide follows [the iCalendar standard, RFC 5545](https://www.rfc-editor.org/rfc/rfc5545). Menus change now and then, so check there if a button has moved.

## Plan around your calendar
Any iCal calendar can show in your week as read-only blocks. [How to link one to Cutline](https://gocutline.com/integrations/ics-calendar/).

## Questions

**Is an .ics file safe?**
The format holds calendar data, not programs. But events can contain links, so treat a file from a stranger the way you would treat their email.

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Cutline: Cutline is a weekly calendar and planner that turns time blocks into XP, levels and streaks. You plan your week in blocks, tick each one off when it is done, and see your progress on a social feed (the Floor) and a weekly leaderboard (the Arena). Planning and budgeting are free; paid plans add a badge, posting, messaging, shared calendars and lower selling fees, from $9 a month. Pro is free to try for 7 days.
Facts: https://gocutline.com/facts/ · Updated 2026-11-06