Now in closed beta
Asta unifies every account into a single timeline — then does what no other calendar can: cross-account shadow blocking. Accept a meeting anywhere and Asta automatically holds the time on all your other calendars, so you're never double-booked across work and personal again.
Native on macOS · iOS · Android · Web
Shadow block — your Acme meeting auto-busies your personal Google & iCloud, so no one double-books you.
The difference: Notion Calendar & Cron show your other calendars. Asta protects them — writing real busy blocks across providers.
See howFeatures
A calendar fast enough to live in, built around the one job other tools leave to you: keeping every account honest about when you're free.
The headline feature. Accept a meeting on any account and Asta writes a private busy block onto your other calendars — across Google, Microsoft, and iCloud. It carries no details, and disappears automatically when the meeting moves or cancels. No other unified calendar does this across providers.
Every calendar from every account, color-coded by source, in one clean day, three-day, and week view. Create and edit events on any account without leaving Asta.
Changes propagate in seconds in both directions. Asta watches each provider for updates and reconciles instantly — no manual refresh, no stale holds left behind.
“When work is busy, block personal.” Set directional rules per account in plain language. Turn protection on for the calendars that matter and leave the rest alone.
A native Mac app, native iOS and Android apps, and a full web app — every one backed by the same engine, so your calendars and rules look identical on every device.
Shadow blocks never copy titles, attendees, or notes. People on your other calendars only ever see that you're busy. Disconnect an account and Asta cleans up the blocks it made.
How it works
Connecting and configuring Asta takes a couple of minutes. After that, it runs quietly in the background across Google, Microsoft, iCloud.
Sign in to Google, Microsoft 365, and iCloud once. Asta pulls every calendar into a single, fast timeline — read and write, not a one-way export.
Decide which accounts should protect which. “When my work calendar is busy, hold the time on personal.” It's a sentence, not a spreadsheet.
Book a meeting anywhere and Asta mirrors a private busy block across your other accounts in seconds — and tidies it up the moment the meeting moves or cancels.
A day in the life
Asta instantly places a no-details busy block at 2pm on your personal Google and your shared iCloud family calendar. Your partner scheduling around you, and the freelancer with a link to your personal availability, both see you as unavailable. Reschedule the client to 3pm and every block follows. Cancel it and they vanish.
2:00 PM — propagated in seconds, removed automatically
Pricing
No credit card, no trial countdown. We're keeping Asta free while we polish it with early users. When paid plans arrive, they'll be one simple flat subscription — no per-account upsells, no enterprise maze.
Everyone who joins the beta keeps founder pricing for good.
FAQ
Still curious? Email hello@astacalendar.com and a human will get back to you.
When you accept a meeting on one account, Asta automatically writes a private “busy” block onto your other calendars — across providers. So a 3pm interview on your work Microsoft account makes you unavailable on your personal Google and iCloud too. Notion Calendar and Cron can overlay calendars, but they can't write protective busy blocks back into a different provider. Asta does, and removes them automatically when the meeting changes.
Google Calendar, Microsoft 365 / Outlook, and Apple iCloud — including multiple accounts of each. Blocking works in every direction between them.
Like any busy hold: it shows your time as unavailable with no details leaked. Titles, attendees, and notes from the original meeting are never copied into the block. Invitees on the other account just see that you're busy.
Yes. The closed beta is completely free — no credit card, no trial clock. When we introduce paid plans later, everyone who joined during the beta keeps founder pricing.
Asta is a native Mac app, native iOS and Android apps, and a full web app — all backed by the same sync engine, so your calendars and rules look identical everywhere.
Asta reads only the calendar data needed to show your events and place busy blocks. The protective blocks Asta creates carry no event details. You can disconnect any account at any time, and Asta removes the blocks it created. See our Privacy Policy for the specifics.
Join the closed beta and be among the first to run one calendar that actually protects your time everywhere — for free, with founder pricing locked in.
