Crab Fit
Calendar & ContactsOpen-source group availability finder for scheduling meetings
Replaces When2meet, Doodle
Easiest Calendar & Contacts to self-host
7 calendar & contacts apps that are easy to get running, ranked by verified deploy effort, project health, and popularity.
Framadate
Calendar & ContactsOnline polling and meeting scheduling tool
Replaces Doodle
DAVx5
Calendar & ContactsCalDAV/CardDAV sync client for Android
Replaces Google Calendar Sync, iCloud sync
Nextcloud Tasks
Calendar & ContactsCalDAV task list app for Nextcloud
Replaces Google Tasks, Todoist
calcurse
Calendar & ContactsText-based calendar and scheduling application
Replaces Google Calendar
InfCloud
Calendar & ContactsWeb client for CalDAV and CardDAV servers
Replaces Google Calendar web
GNOME Calendar
Calendar & ContactsSimple desktop calendar with CalDAV support
Replaces Google Calendar
No apps match these filters.
The shortlist at a glance
| App | Deploy effort | Difficulty | Min. RAM | License | ★ Stars |
|---|---|---|---|---|---|
| Crab Fit | Under-an-hour setup | Easy | 256 MB | MIT | 532 |
| Framadate | Under-an-hour setup | Easy | 128 MB | CECILL-B | 600 |
| DAVx5 | Read-the-docs project | Easy | 128 MB | GPL-3.0 | 2,949 |
| Nextcloud Tasks | Read-the-docs project | Easy | 512 MB | AGPL-3.0 | 707 |
| calcurse | Read-the-docs project | Easy | 16 MB | BSD-2-Clause | 1,308 |
| InfCloud | Read-the-docs project | Easy | 32 MB | GPL-3.0 | 89 |
| GNOME Calendar | Read-the-docs project | Easy | 256 MB | GPL-3.0 | 300 |
Last reviewed Oct 11, 2026 · 628 words
The easiest calendar server to self-host is not on this list. Everything ranked here is either a client (DAVx5, calcurse, GNOME Calendar, InfCloud) or a meeting-poll tool (Crab Fit, Framadate), because the directory files CalDAV servers under groupware. The least painful first install for a beginner is Radicale (Easy, 64 MB by the directory's estimate) on the server, with DAVx5 on Android. Read this list as the shopping list for everything around that server.
Why the top two are poll tools
The ranking sorts by verified deploy effort, and the only entries here with a published Docker image are Crab Fit and Framadate, both at "under an hour". Neither stores a calendar. Crab Fit draws an availability heatmap so a group can find a meeting slot without anyone registering; Framadate runs date and decision polls and has done since 2011. They replace When2meet and Doodle, not Google Calendar. If your actual pain is "eight people, one dinner date", install Crab Fit and stop there.
The other five carry the "read-the-docs" badge because there is no container to deploy: they are apps you install on a phone, desktop, or web host.
| Pick | What it is | RAM estimate | Runs where |
|---|---|---|---|
| Crab Fit | Group availability finder | 256 MB | Docker on your server |
| Framadate | Date and decision polls | 128 MB | Docker or PHP host |
| DAVx5 | CalDAV/CardDAV sync for Android | 128 MB | Your phone |
| InfCloud | Web calendar for a CalDAV server | 32 MB | Any static web host |
| calcurse | Terminal calendar with CalDAV sync | 16 MB | Your terminal |
What "easy" still leaves you to do
Radicale installs in minutes, but four jobs remain. Persistence: its storage is plain files, so mount that directory on a volume you control, or a container rebuild wipes your calendars. HTTPS: phones will push your contacts and appointments to this server, so put it behind a reverse proxy with a real certificate before you add the first device, as covered in the reverse proxy showdown. Accounts: create one login per person, since CalDAV clients authenticate per user and shared logins make shared calendars impossible to untangle later. Backups: plain files back up with anything, so add the storage folder to whatever already backs up your server.
If you want a browser view of your calendar, InfCloud is the light answer: static files, 32 MB, and it works with Radicale and Baïkal. Nextcloud Tasks appears in this list too, but it is an add-on for an existing Nextcloud, not a standalone install.
How much RAM does a self-hosted calendar need?
Very little. Radicale plus InfCloud sits under 100 MB by the directory's estimates, and adding Crab Fit for scheduling keeps the whole set under 512 MB. A Raspberry Pi or the smallest VPS tier you can find has room to spare. The clients run on devices you already own, so they cost the server nothing.
When to step up
Move to EteSync (Medium, 256 MB) when the contents of your calendar are sensitive enough that a plaintext server worries you; you trade generic clients for end-to-end encryption. Move to Cal.diy (Medium, 512 MB, no container path in the catalogue) when the goal becomes public booking pages rather than a private calendar. Move to Nextcloud only if you want files, contacts, and calendars in one web interface and accept running a much larger application to get it.
What I'd do
Radicale on a mounted volume, behind HTTPS, one account per family member, DAVx5 on every Android phone. Add Crab Fit the first time a group chat spends a day picking a date. That is the whole first install, and it should take an evening.