Share Your Outlook Calendar as Free/Busy Only (Availability, Not Details)

You want colleagues or family to see when you're free, but not what fills your day. Outlook already ships the tool for this — it's the permission level you choose when you publish, not a separate feature. Pick the right one and the feed carries only availability.

Outlook's built-in availability levels

When you publish a Microsoft 365 (Office 365) calendar, Outlook asks how much each subscriber may see. The relevant choices are:

• "Can view when I'm busy" — the availability-only level. The feed contains time blocks marked busy/free, with generic titles (usually just "Busy"). Titles, locations, descriptions and attendees are stripped by Outlook before the feed ever leaves the server.
• "Can view titles and locations" — a middle level; times plus event titles.
• "Can view all details" — the full feed, everything included.

For a free/busy share, publish with "Can view when I'm busy". Because the filtering happens on Microsoft's side, subscribers genuinely cannot recover the hidden fields — they were never sent.

Steps

1. In Outlook on the web, go to Settings → Calendar → Shared calendars.
2. Under Publish a calendar, choose the calendar and set permission to "Can view when I'm busy".
3. Publish, then copy the .ics (ICS) link — not the HTML one. (Where to find it.)

Where CalConverter fits — and where it doesn't

The availability-only feed still has Microsoft's format quirks: Windows time-zone names and missing VTIMEZONE blocks that make Google and Apple show the busy blocks at the wrong times. CalConverter cleans that up so the free/busy feed subscribes reliably.

Be clear on what the converter does not do: CalConverter has no detail-stripping filter of its own (yet). The privacy here comes entirely from Outlook's "when I'm busy" level. If you publish "Can view all details" and expect us to hide the titles, that isn't a feature we offer today. Choose the availability level at publish time.

If you need per-event control instead

Outlook's levels are all-or-nothing for a whole calendar. If you want a normal detailed calendar for yourself but a stripped one for others, the usual workaround is a second, sharing-only calendar. See also Share your work calendar without showing the details, which tracks the privacy filter we're building.