Radicale by Kozea
A simple CalDAV (calendar) and CardDAV (contact) server.
About Radicale
From the project's README at github.com/Kozea/Radicale. Lightly cleaned for readability; for the full source see the upstream repo.
[](https://github.com/Kozea/Radicale/actions/workflows/test.yml) [](https://coveralls.io/github/Kozea/Radicale?branch=master)
Radicale is a small but powerful CalDAV (calendars, to-do lists) and CardDAV (contacts) server, that:
Shares calendars and contact lists through CalDAV, CardDAV and HTTP. Supports events, todos, journal entries and business cards. Works out-of-the-box, no complicated setup or configuration required. Can limit access by authentication. Can secure connections with TLS. Works with many CalDAV and CardDAV clients Stores all data on the file system in a simple folder structure. Can be extended with plugins. Is GPLv3-licensed free software.
For the complete documentation, please visit Radicale master Documentation.
Health score breakdown
6-dimension composite. See methodology for formula and weights.
Adoption signals
Real-world usage data, pulled from each registry. The bigger the numbers, the more battle-tested the project.
| Signal | Value | Source |
|---|---|---|
| GitHub stars | 4.6k | github.com/Kozea/Radicale |
| GitHub forks | 505 | github.com/Kozea/Radicale |
| Docker Hub pulls | 16k | hub.docker.com / kozea |
| PYPI downloads (last month) | 20k | radicale |
Release & maintenance
Is this project actively maintained, or about to die? Check the recency of last commit and last release.
| Project age | 14.7 years | since Aug 2011 |
| Last commit | 3 days ago | May 4, 2026 |
| Releases shipped | 74 | last: 8 days ago |
| Funding links | 1 | declared by maintainers |
Self-hosting cost across providers
Detected requirements: 4GB RAM, 40GB disk minimum. Cheapest plan per provider that meets the requirement.
| Provider | Plan | Specs | Monthly | |
|---|---|---|---|---|
| hetzner | CAX11 | 2c · 4GB · 40GB | $4.13 USD | Deploy → |
| vultr | VC2 | 1c · 1GB · 25GB | $5 USD | Deploy → |
| linode | Nanode 1GB | 1c · 1GB · 25GB | $5.12 USD | Deploy → |
| digitalocean | Basic Regular 1GB | 1c · 1GB · 25GB | $6 USD | Deploy → |
Security advisories
GHSA-84cw-mxhv-qvv4. What people say on Hacker News
- Nuclear Fusion tokamak simulator FUSION CIRCUS beta
- Extracting experiments from materials science literature
- LA's levitating amoeba: a new kind of museum
- SoftBank, Intel to develop ZAM memory – new memory designed as lower-power HBM
- Radicle is an open source, peer-to-peer code collaboration stack built on Git
Ready to self-host Radicale?
Spin up a hetzner CAX11 (4GB RAM, 40GB disk) for $4.13/mo and follow the project's official install docs.
Data last refreshed May 7, 2026.
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