Fastmail Calendar vs Musubi
Fastmail Calendar
fastmail.comMusubi
musubi.proSide by side
| Figure | Fastmail Calendar | Musubi |
|---|---|---|
| Price from | $4/mo | Free |
| Free plan | — | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | — |
| macOS | Yes | — |
| Linux | Yes | — |
| iOS | Yes | Yes |
| Android | Yes | Yes |
| Self-hosted | — | Yes |
| Plans published | 6 | 1 |
| Spec score · Calendar apps | 9.0 (#11) | 8.6 (#37) |
| Calendar sync | two_way | two_way |
| Free plan | No | Yes |
| Headquarters | Melbourne, Australia | Brno, Czech Republic |
| Integrations | Fastmail describes integrations with 1Password and Bitwarden for creating Masked Email addresses, and the pricing page mentions integrations including 1Password and Dropbox. | Musubi connects to Google Calendar, Apple iCloud, Outlook and Microsoft 365, and compatible CalDAV services such as Nextcloud, Fastmail, and Radicale. |
| Mobile apps | ios and android | ios and android |
| Platforms | Fastmail lists apps for Windows, macOS, Linux, iOS, and Android, as well as a browser app. | The desktop web app and Android app are available; iOS is in beta through TestFlight. |
| Security | Fastmail says data is encrypted at rest and in transit, supports two-step verification and passkeys, and offers EU or US data residency choices. | The hosted app and primary database run in Germany, connections use HTTPS/TLS, and certain provider credentials receive application-level authenticated encryption. |
| Shared calendars | Yes | Users can invite selected people to a shared calendar and grant view or edit access. |
| Support | Every plan includes expert support from real people, and the pricing page says support is available 24/7. | The maker says product questions and support requests can be sent by email, and it also provides feedback and community links. |
Plans
Fastmail Calendar
- Basic$4 a month
- Individual$6 a month
- Standard$6 a month
- Duo$10 a month
- Professional$10 a month
- Family$14 a month
In their own words
Fastmail Calendar
Fastmail Calendar is an online calendar integrated with Fastmail email, available on web, Linux, macOS, Windows, Android and iOS. It supports two-way calendar sync and shared calendars, including business plans with sharing and administrative controls. Users can bring in calendars from Google, iCloud and elsewhere, search instantly, and organize events with drag-and-drop editing. It can show schedules in other time zones, compare emailed event updates with earlier versions, and manage calendars offline in its apps; changes sync when the device is back online. Fastmail documents calendar access through CalDAV and JMAP APIs for account data more broadly. The service is paid, has a 30-day trial and does not list a free plan. Options include Basic at $4 a month, Individual at $6 a month, Standard at $6 a month, Duo at $10 a month, Professional at $10 a month and Family at $14 a month. Longer billing terms have separately listed rates. Fastmail was founded in 1999 and is headquartered in Melbourne, Australia.
Musubi
Musubi is a shared calendar that combines calendars, tasks, and people for everyday planning. Events can appear in multiple calendars, with one update reflected wherever they are shown. It connects with Google Calendar, Apple iCloud, Outlook, Microsoft 365, and compatible CalDAV services including Nextcloud, Fastmail, and Radicale. Synchronization works both ways where provider permissions allow, while read-only calendars remain read-only. Views cover day, week, month, and agenda formats, and personal pages control which calendars and items appear. Tasks sit beside events with status, priority, due dates, and web list or Kanban views. Android and iOS apps provide mobile access; Android adds agenda and month widgets, with reminders scheduled on the device. Musubi is open source under the MIT License and can be self-hosted with Docker Compose v2, a domain, and HTTPS. Hosted Musubi costs nothing during early access. The hosted app and primary database run in Germany.