OSI-licensed only · self-hostable

Open-Source Calendly Alternatives (2026)

Calendly lets people book time on your calendar through a shareable link, with availability rules, reminders and calendar sync. Open-source schedulers do the same and let you keep bookings and calendar credentials on your own server.

Every tool below is under an OSI-approved licence (MIT, Apache-2.0, MPL-2.0, GPL-3.0 or AGPL-3.0), checked against its repository. Cal.diy, the community fork of Cal.com, is included with the limits its own README describes.

Licences checked against each repository on November 7, 2026.

What you're replacing

  • •Shareable booking pages with availability rules
  • •Two-way calendar sync and conflict checks
  • •Email confirmations, reminders and rescheduling
  • •Group polls and finding a time that works

At a glance

ToolBest forLicenceRuns as
Cal.diyCommunity scheduling platform, fork of Cal.comMITDocker
Easy!AppointmentsAppointments for service businessesGPL-3.0Server
TymeslotBooking pages with broad calendar and video supportAGPL-3.0Docker
Thunderbird AppointmentSimple booking from the Thunderbird teamMPL-2.0Docker
CalnodeLean scheduling engine with team routingApache-2.0Docker
Nextcloud CalendarBooking inside an existing NextcloudAGPL-3.0Server
RalllyGroup polls for finding a meeting timeAGPL-3.0Docker

1. Cal.diy

MIT

Best for: Community scheduling platform, fork of Cal.com

The community-driven, open-source scheduling platform, MIT-licensed with no commercial or enterprise code. Integrates with Google Calendar, Microsoft Graph, Zoom, Daily and more, and self-hosts with Docker Compose or one-click platforms. There is no hosted version.

Strengths

  • + Fully MIT-licensed, no licence key
  • + Calendar and video integrations
  • + Docker Compose and one-click deploys

Trade-offs

  • − README recommends it for personal, non-production use at your own risk
  • − Teams, Organizations, Insights, Workflows and SSO/SAML were removed
RepositoryWebsite

2. Easy!Appointments

GPL-3.0

Best for: Appointments for service businesses

A powerful, self-hosted appointment scheduling platform with appointment and customer management, services and providers, working plans, Google Calendar sync and email notifications. Production setup needs Apache or Nginx, PHP 8.2+ and MySQL.

Strengths

  • + Services, providers and working plans
  • + Google Calendar synchronisation
  • + Multi-language interface

Trade-offs

  • − Traditional PHP and MySQL install
  • − Less polished booking-page design than Calendly
RepositoryWebsite

3. Tymeslot

AGPL-3.0

Best for: Booking pages with broad calendar and video support

Scheduling software that stays yours: booking pages, calendar sync, video rooms and automated emails on your own server. Syncs with Google, Outlook, iCloud, CalDAV and Nextcloud, supports Google Meet, Teams, Zoom and Jitsi, and offers embeddable widgets.

Strengths

  • + Two-way sync checks double-booking across calendars
  • + Embeddable inline, popup or floating widgets
  • + Single Docker container with bundled Postgres

Trade-offs

  • − Built on Elixir/OTP, an unfamiliar stack for many teams
  • − Paid bookings via Stripe Connect are optional and off by default
RepositoryWebsite

4. Thunderbird Appointment

MPL-2.0

Best for: Simple booking from the Thunderbird team

Invite others to grab times on your calendar: choose a date and make appointments as easy as it gets. Offers availability setup, a bookers page and booking management. Docker is the recommended and only supported way to build it.

Strengths

  • + Simple booking flow
  • + Availability and booking management
  • + OIDC login with Thunderbird Accounts

Trade-offs

  • − Docker is the only supported setup method
  • − Self-hosting runs five containers
RepositoryWebsite

5. Calnode

Apache-2.0

Best for: Lean scheduling engine with team routing

A lean, self-hostable scheduling engine. Supports event types, availability rules, team routing (round-robin, collective, priority), Google, Microsoft 365, CalDAV and Zoom integrations, Stripe bookings and a REST API with webhooks. Run it with one Docker command or the Go binary.

Strengths

  • + Round-robin and collective team routing
  • + Single Go binary or Docker with SQLite
  • + Embeddable booking widget and REST API

Trade-offs

  • − Younger project with a smaller community
  • − Built-in video meetings need a LiveKit endpoint
RepositoryWebsite

6. Nextcloud Calendar

AGPL-3.0

Best for: Booking inside an existing Nextcloud

A calendar app for Nextcloud that syncs events from various devices and edits them online. Its README lists appointment booking, letting people book an appointment with you using the separate Appointments app.

Strengths

  • + Fits into an existing Nextcloud setup
  • + Syncs events from multiple devices
  • + Appointment booking supported

Trade-offs

  • − Requires a Nextcloud instance
  • − Booking needs the separate Appointments app
RepositoryWebsite

7. Rallly

AGPL-3.0

Best for: Group polls for finding a meeting time

An open-source scheduling tool that helps you find the best date and time to meet. Participants vote without an account, an availability grid shows everyone's responses, and the chosen date is finalised and sent to everyone. Ships as a Docker image.

Strengths

  • + No account needed for participants
  • + Availability grid and comments
  • + Docker image

Trade-offs

  • − Group polling rather than one-to-one booking links
  • − No calendar-sync booking pages
RepositoryWebsite

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How to choose

If you need…Start with
A Calendly-style booking page with the widest integrationsCal.diy or Tymeslot
Appointments for a clinic, salon or service businessEasy!Appointments
Team scheduling with round-robin routingCalnode
Booking that lives inside your NextcloudNextcloud Calendar
Finding a time for a group meetingRallly
A simple booking tool from the Thunderbird projectThunderbird Appointment

Open-source Calendly alternatives: FAQ

Quick answers to common questions

Is there an open-source alternative to Calendly?

Yes. Cal.diy (MIT), Tymeslot (AGPL-3.0), Easy!Appointments (GPL-3.0) and Calnode (Apache-2.0) are self-hostable scheduling tools with booking pages and calendar sync.

Is Cal.com open source?

Cal.com's public repository is now Cal.diy, which its README describes as fully MIT-licensed with no commercial or enterprise code, unlike Cal.com's earlier open-core model. The README also says it is recommended for personal, non-production use.

Which Calendly alternative supports team round-robin scheduling?

Calnode lists team routing with fixed, round-robin, collective and priority modes. Cal.diy removed its team features in the community edition.

Can I self-host a Calendly alternative without a database server?

Calnode can run from a Go binary or Docker with a persistent SQLite volume, and Tymeslot ships a single Docker container with bundled Postgres. The others need MySQL or Postgres.

What is the difference between Rallly and Calendly?

Rallly is a group poll tool: you propose several times and participants vote. Calendly-style booking pages let one person publish availability for others to book directly, which Cal.diy, Tymeslot and Calnode provide.

Maintain an open-source Calendly alternative?

List it on TechLogHub and we'll review it for this page.

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