Sync Google, Outlook & Apple calendars. Keep events private. | Caltsu

You run work on Outlook and life on Google Calendar. Maybe three client accounts plus personal iCloud. Either way: double bookings, leaked event titles, your dentist on the team calendar. Caltsu syncs busy/free times across Google, Outlook, and Apple calendars—bidirectionally, in real-time—without copying event details between accounts. Two-minute setup. Runs silently in the background. Free: 2 accounts, one-way sync. Pro (€7/mo): 10 accounts, unlimited rules, webhooks, bidirectional.

Framer — Launch websites with enterprise needs at startup speeds.

Launch websites with enterprise needs at startup speeds.

Hey PH 👋 I built Caltsu because I was tired of the “sorry, that was on my other calendar” conversation. As a freelancer, I juggle multiple client Outlook accounts alongside a personal Google Calendar. Every multi-calendar tool I tried either: 1. Copied my full event titles across accounts (a privacy nightmare). 2. Synced on a 15-minute delay, which is useless when someone books a slot in the gap. 3. Tried to be an AI scheduling assistant when I just needed to know my actual availability. Caltsu blocks off your busy times across calendars without exposing what you’re doing. Webhook-based sync means it’s nearly instant. And privacy controls mean your therapy appointment stays between you and your therapist. The free plan covers 2 accounts. Pro is €7/mo if you need more. I’d love your feedback—especially from anyone else managing 3+ calendar accounts. What broke for you with other tools?

Framer — Launch websites with enterprise needs at startup speeds.

Launch websites with enterprise needs at startup speeds.