What is CalDAV?

CalDAV is the web standard calendaring extension for the WebDAV. It allows CalDAV clients to access, manage, sync and schedule calendar events and calendars on servers.

CalDAV synchronizes calendar data across different devices.

In this list, we preview some of self-hosted CalDAV servers and clients that anyone can download, setup and use on their local machines or servers.

OS CalDAV servers

1- Sabre

Sabre is the most popular WebDAV framework for PHP. Use it to create WebDAV, CalDAV and CardDAV servers.

Sabre is the parent project of Baikal CalDAV server, as it also offers several similar tools for developers, and companies to use.

2- Baïkal

Baïkal is a lightweight CalDAV+ CardDAV server. It offers an extensive web interface with easy management of users, address books and calendars. It is fast and simple to install and only needs a basic PHP capable server.

The data can be stored in a MySQL or a SQLite database, it is up to the user to configure its preferable database store.

You can find all of its features in our snap review here.

Baïkal: Have your own CalDav and CardDav server
What are CalDav and CardDav?CalDav is an internet standard and protocol used to sync calendars across devices and services. It is often used to sync your calendar events between your calendar apps, webmail, devices and services. CardDav or vCard is an address book client/ server protocol and standa…
MEDevel.comHamza Musa

3- Bedework

Bedework is an open-source enterprise calendar system that supports public, personal, and group calendaring. It offers a CalDAV server, CardDAV server, and web clients.

It is designed to conform to the current and recent calendaring standards with a goal of attaining strong interoperability between other calendaring systems and clients.

Bedework provides a full CalDAV server. It can be used with any CalDAV capable client and has been shown to work with Mozilla Lightning, the iPhone, Apple's iCal, Evolution, and others.

It supports import and export, multiple calendars, comes with RSS and JSON feeds, and supports several calendar standards out-of-the-box.

5- Xandikos

Xandikos is a lightweight yet complete CardDAV/CalDAV server that backs onto a Git repository of your choice, either on a Git service like GitHub, and GitLab or a self-hosted Git service.

The supported clients include: Evolution, DAVDroid, Akondadi, AgendaV, CardBook, CalDAV-Sync, Apple iOS, sogo connector for Icedove/Thunderbird, and Tasks app.

Xandikos can run directly within Linux using Systemd, or within Docker or Kubernetes.

6- kcaldav

kcaldav is a simple, safe, and minimal CalDAV server depending only on kcgi, sqlite3, and expat.

kcaldav is designed for simple setups, like sharing a calendar collection between Mozilla Lightning, Mac OS X iCal, DAVdroid forks, and iOS (iPhone) clients. It compiles and runs on OpenBSD, Linux, NetBSD, FreeBSD, Mac OS X, Solaris, and OmniOS.

It is an open source project with friendly, auditable source code.

All sources use the ISC (like OpenBSD) license. See the LICENSE.md file for details.

7- Calendar Server

The open source Calendar and Contacts Server project is a standards-compliant server implementing the CalDAV and CardDAV protocols.

Calendar Server provides a shared location on the network allowing multiple users to store and edit calendaring and contact information.

8- Dockermail

Dockermail is a ready-to-use email server + (optional) web mail + (optional) CalDav, CardDav and a kitchen sink in a docker container.

It is a secure minimal-configuration mail server in a docker container, including a free webmail client.

9- DavMail

DavMail is a multiprotocol  email gateway allowing users to use any mail client with Exchange and Office 365, even from the internet through Outlook Web Access on any platform, tested on MacOSX, Linux and Windows.

Beside its support for the email protocols as POP, IMAP, and SMTP, it also supports CalDAV, and CardDav as well as LDAP protocols.

10- CalDavZAP

CalDavZAP is an open source self-hosted CalDAV web client implementation released under GNU Affero General Public License (version 3.0), that anyone can install locally or on their remote servers.

11- Outlook CalDav Synchronizer

This is not an actual CalDAV server, it is a tool that helps you sync your events, contacts, and tasks tasks between other apps.

Outlook CalDav Synchronizer is a free open-source Outlook Plugin, which synchronizes data between Outlook and Google, SOGo, Nextcloud or any other CalDAV or CardDAV server. Supported Outlook versions are Office 365, 2019, 2016, 2013, 2010 and 2007.

SOGo: A Free open-source enterprise-grade Webmail and Groupware Server for teams
SOGo is an open-source groupware and IMAP/ SMTP webmail client for teams and enterprise. The interface design follows Material design system which gives it a pro look and makes it more comfortable and productive for every-day use. It is responsive, reactive and real-time interface with full drag-an…
MEDevel.comHamza Musa

12- Fennel.js  

Fennel.js is an open-source free lightweight CalDAV and CardDAV server, that anyone can download, install and run on their local machine or a remote servers.

The project is written entirely in JavaScript, but the team is working on porting it to the Go programming language.

Fennel.js supports TLS, and can be installed easily with Nginx, and comes with a built-in Authentication that uses CourierAuth.

Fennel.js uses SQLite, but you can easily use other SQL database engines like MySQL, MariaDB, and PostgreSQL.

The project with the source code is released under the AGPL-3.0 License.


Final thought

Open-source CalDAV servers allows users to take control of their data and ensure its privacy and security. However, we encourage you to go through their features to choose the right one for you.

If you know of any other solution that fits our list, let us know.