Files with ics extension are calendar data in exchange format which is widely accepted in many personal information managers and e-mail clients such as Microsoft Outlook, or Apple iCal. It is an universal format for transporting calendar data and events from one program to another.

There are 4 other file types using
the ICS file extension!

empty icon.ics - Image Cytometry Standard

empty icon.ics - IronCAD 3D CAD data

empty icon.ics - SwiftView command data

empty icon.ics - Sony IC Recorder sound

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ICS file extension - iCalendar calendar file format (Microsoft Outlook, Apple iCal)

What is ics file? How to open ics files?

File type specification:

Settings, options, themes or skins file type icon Settings, options, themes or skins file type

ics file icon: ics filetype icon

File extension ics is mainly associated with Microsoft Outlook, a personal information manager, which is part of Microsoft Office, developed by Microsoft Corporation. But the ICS format is widely used by many other applications.

The ics file format is universal calendar format used by many other applications such as Microsoft Outlook, Apple iCal (Calendar), Mozilla Sunbird, and Google Calendar.

It allows users to publish and share calendar data on internet. Other users can subscribe to published calendars and import events into their own calendars. The specifications for this format are described in RFC 2445.

MIME types:

Updated: January 24, 2023

The default software associated to open ics file:

Microsoft Outlook icon

Microsoft Corporation logoMicrosoft Outlook  Microsoft Windows software

Company or developer:
Microsoft Corporation

Microsoft Outlook is e-mail management tool and personal information manager distributed with Microsoft Office suite. Outlook integrates e-mail application, calendar, task manager, contact manager, note taking in to one application.

Microsoft Outlook is used as a stand-alone application and also can work with Microsoft Exchange Server and SharePoint Server.

The predecessor of Outlook was called Schedule+. The newest version is called Outlook 2016.

Apple Calendar (iCal) icon

Apple, Inc. logoApple Calendar (iCal)  Apple macOS / Mac OS X software

Company or developer:
Apple, Inc.

Apple Calendar (iCal) is a personal calendar application bundled with Apple Mac OS X since 2002. Calendar was the first calendar application for Mac OS X to offer support for multiple calendars and the ability to publish/subscribe calendars to WebDAV server.

Help how to open:

Applications like Microsoft Outlook or Apple iCal are able to import *.ics files.

How to convert:

ABC Amber iCalendar Converter supports conversion of ICS Outlook calendar files in to other document formats (PDF, HTML, CSV, XLSX, etc.).

Find conversions from ics file:

ics to csv

ics to pdf

ics to png

ics to pst

ics to xls

ics to xlsx

ics to xml

Find converter to ics file type:

csv to ics

html to ics

icbu to ics

pdf to ics

pst to ics

vcf to ics

xml to ics

File identification strings:

HEX code: 42 45 47 49 4E 3A

Related links:

iCalendar format full overview.

List of software applications associated to the .ics file extension

Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open ics file, edit ics file, convert ics file, view ics file, play ics file etc. (if exist software for corresponding action in's database).

Click on the tab below to simply browse between the application actions, to quickly get a list of recommended software, which is able to perform the specified software action, such as opening, editing or converting ics files.

Software that open ics file - iCalendar calendar file format (Microsoft Outlook, Apple iCal)

Programs supporting the exension ics on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about listed programs for open ics file action.

Microsoft Windows:

Main software associated with ics file by default:
Microsoft Outlook small icon Microsoft Outlook
Other suggested software:
Lightning small icon Lightning

Apple macOS / Mac OS X:

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