2 self-hosted Exchange alternatives

Exchange is a popular proprietary tool in the calendar & contacts space. These open-source apps let you replace Exchange with software you host and control yourself.

Best self-hosted Exchange alternatives

Hard

bare-metalsource

Tasks.org Server alt nono Calendarserver

Calendar & Contacts

Standards-compliant calendar and scheduling server

Replaces Google Calendar, Exchange

★ 506 Hard setup Apache-2.0

Horde Kronolith

Calendar & Contacts

Calendar application from the Horde groupware suite

Replaces Google Calendar, Exchange

★ 10 Hard setup GPL-2.0

Compare Exchange alternatives

Horde Kronolith vs Tasks.org Server alt nono Calendarserver

Switching from Exchange

Moving off Exchange means trading a managed subscription for a service you run yourself. The payoff is ownership: no per-seat pricing, no vendor lock-in, and full control of your data. Start with the option above that matches your setup-difficulty comfort level — every app links to a detailed specs page and head-to-head comparisons.