Calendar Liberator by fabiocchetti

Calendar Liberator exports the events from your Outlook Web calendar into a standard .ics (iCalendar) file, so you can import your work schedule into Google Calendar, Apple Calendar, Fastmail, Proton Calendar, Thunderbird or any app that reads calendar files — and finally see work and personal life side by side.

WHY CALENDAR LIBERATOR

Many companies will only sync your work calendar to your phone if you enrol the device in their mobile device management (Intune/MDM), which means handing over a degree of control of a personal device and granting access to your entire Microsoft account. If you would rather not do that, the usual alternatives are retyping every meeting by hand, or going without.

Calendar Liberator takes a third road. It asks for no password, connects to no Microsoft API, registers no OAuth application, and runs no server. It reads the calendar you are already looking at, in the browser session you have already signed into, and writes it to a file on your own disk. Nothing leaves your computer.

HOW IT WORKS

1. Open your calendar in Outlook on the web and sign in as you normally would.
2. Click the Calendar Liberator icon in the toolbar.
3. Check the calendar name and timezone (both auto-detected) and decide whether to include declined and out-of-office events.
4. Click "Export .ics".
5. The extension walks through a 28-day window — 7 days back and 21 days ahead — in week view, collects the events it can see, then restores your original view and returns to today.
6. Import the downloaded .ics file into whichever calendar app you use.

WHAT GETS EXPORTED

• Event title
• Date, start time and end time
• All-day and multi-day events
• Organiser name and the location or room shown on the event, when Outlook displays them
• Busy / free / tentative status
• A note marking recurring instances

And nothing else. No attendee lists, no invitation bodies or meeting notes, no attachments, no email addresses, no message content. The extension only ever reads the calendar grid — it never touches your mailbox, your files or your contacts.

PRIVACY BY DESIGN

• No data collection of any kind
• No external network requests: no backend, no analytics, no telemetry, no ads
• No accounts, no credentials, no OAuth tokens
• Nothing is written to storage — the events exist only in memory during the export, then become the file you download
• Permissions limited to activeTab plus host access to Outlook and Office 365 domains. The extension cannot see any other website
• Fully open source under the MIT licence, so every claim above can be verified line by line

TIMEZONES DONE PROPERLY

You pick the IANA timezone that matches the times shown in Outlook — your browser's zone is preselected. Each event is converted using the correct daylight-saving offset for its own date, so meetings land at the right hour even when the export spans a clock change. All-day events are exported as floating dates and never shift.

WORKS WITH

• outlook.office.com and outlook.office365.com
• outlook.com and Microsoft 365 tenants on office.com
• Corporate MCAS / Defender for Cloud Apps proxy domains
• Chrome, Edge, Firefox, Brave, Opera and other Chromium browsers

IMPORT IT ANYWHERE

• Google Calendar — Settings, then Import & export
• Apple Calendar and iCloud — File, then Import
• Thunderbird, Fastmail, Proton Calendar, Zoho, and any other iCalendar-compatible app

PERFECT FOR

• Seeing work meetings next to personal appointments on your own phone
• Keeping a personal device free of corporate device management
• Contractors and consultants juggling more than one organisation's calendar
• Sharing your availability without sharing your mailbox
• Keeping an offline snapshot or backup of your schedule

GOOD TO KNOW

• The Outlook interface must be set to English.
• The export covers 28 days (7 back, 21 ahead), not your whole calendar history.
• The .ics is a snapshot, not a live subscription: run the export again whenever you want fresh data. Advanced users can host the file themselves for automatic refresh — the GitHub README explains how.
• The extension reads Outlook's web interface, so a major redesign by Microsoft can break it until an update ships.
• It is read-only. It can never create, edit or delete anything in your Outlook calendar.
• Always check the imported result before relying on it for something important.

OPEN SOURCE

Source code, issue tracker and roadmap: https://github.com/fabiocchetti/calendar-liberator
Privacy policy: https://visiomultimedia.com/en/extensions-privacy-policy/#calendar-liberator

Calendar Liberator is an independent project. It is not affiliated with, endorsed by, or sponsored by Microsoft. Outlook, Office 365 and Microsoft 365 are trademarks of Microsoft Corporation; Google Calendar is a trademark of Google LLC; Apple Calendar is a trademark of Apple Inc.