Other calendars see Busy. Not the meeting.
For every event, Caltsu writes a plain Busy block into your other calendars, across Google Workspace and Microsoft 365.
Works with the calendar accounts you already have
- Google Workspace
- Gmail
- Microsoft 365
- Outlook.com
What the other calendar receives
One personal appointment, field by field. The left column stays in your Google calendar. The right column is everything written to the client's Microsoft 365, including the name of the calendar the block came from.
- Title
- YoursDentist, Dr. SaloClientBusy
- Start and end
- YoursTue 08:30-09:15ClientTue 08:30-09:15
- Attendees
- YoursYou, Dr. SaloClientNot copied
- Location
- YoursKamppi clinicClientNot copied
- Your notes
- YoursBring referral letterClientNot copied
- Block description
- YoursNoneClientBlocked time from Personal
- Meeting link
- YoursNoneClientNot copied
Here the Google calendar was renamed to Personal. Without a rename, the block description shows the account's email address.
For people who answer to more than one organization
Consultants in client tenants. You have an account in each client's Microsoft 365. Each client sees you as busy when another client has you booked, and does not see who that client is, as long as the source calendar's name does not say it.
Employees with a life outside work. Your personal Google calendar blocks time in the company calendar. Colleagues can book around the dentist without reading about it.
People running more than one company. Two or three company calendars behave as one for availability, while each board keeps its own details.
Setting it up
- 1
Connect
Sign in to each Google or Microsoft account with the provider's own consent screen. Caltsu never sees a password.
- 2
Pick calendars
Choose which calendars belong together. Every event in one of them becomes a Busy block in the others.
- 3
Leave it running
New, moved and cancelled events update the blocks within seconds through Google and Microsoft push notifications.
Something to forward to your IT team
If your organization reviews calendar apps before you can connect them, these are the facts they will ask for.
- No passwords. Access runs through Google and Microsoft OAuth consent, scoped to calendars.
- Database in the EU. PostgreSQL in Frankfurt. The company is DataDux Oy in Helsinki.
- Revocable at any time. Remove access from the Google or Microsoft account page, or disconnect the account in Caltsu, which deletes its tokens.
- calendar.events
- calendar.readonly
- openid email profile
- Calendars.ReadWrite
- offline_access
- openid email profile
One plan, every feature
Unlimited accounts, calendars and sync rules. Try it for 14 days without a card.
€5per monthor €48 per year
See pricingQuestions
Can the other calendar see what my event is about?
No. The block Caltsu creates has a start time, an end time, a title that defaults to Busy, and a one-line description naming the source calendar. The event's own title, attendees, location, notes and meeting link are never written to the other calendar.
Do I need admin approval in my company's Microsoft 365?
It depends on your tenant. Some organizations let users consent to calendar apps themselves, others require an administrator to approve the app first. The security page lists the exact permissions to send to your IT team.
Does it work with Apple iCloud calendars?
Not yet. Caltsu supports Google (Workspace and Gmail) and Microsoft (Microsoft 365 and Outlook.com) today.
What happens to the blocks if I stop?
Removing a sync rule removes the blocks it created. Disconnecting an account deletes the tokens Caltsu holds for it. Deleting your Caltsu account removes the blocks and cancels the subscription. The security page lists exactly what is kept.
Where is my data stored?
In a PostgreSQL database in Frankfurt, Germany, run by DataDux Oy in Helsinki.