Best Open Source Alternatives to Calendly in 2026
Calendly's Per-Seat Pricing Adds Up Fast
Calendly Standard costs $10/user/month (billed annually). Teams runs $16/user/month. Enterprise starts at $15,000/year flat. For a 20-person sales team on the Teams plan, that's $3,840/year. At 100 users, you're past $19,200 annually.
And the free tier is barely functional -- one event type, no integrations beyond basic calendar sync, no team scheduling, no routing. The moment you need more than a single booking link, you're on a paid plan.
Calendly's free plan limits you to one active event type and strips out workflows, reminders, integrations, and team features. For any team doing real scheduling -- sales, support, hiring -- you're forced to pay immediately.
Open source scheduling tools give you unlimited event types, full calendar integration, team scheduling, and self-hosted deployment -- often at zero software cost. Here are the best options in 2026.
TL;DR
Cal.com is the best overall Calendly alternative -- most feature-complete, most active community, and the closest to matching Calendly's workflow end-to-end. For service businesses that need appointment booking with multiple providers (salons, clinics, consultancies), Easy!Appointments is purpose-built and simple. If you just need to find a time that works for a group, Rallly does meeting polls better than anything else.
Key Takeaways
- Cal.com (39K+ GitHub stars) is the most popular open source scheduling platform. Round-robin, routing forms, workflows, 70+ integrations, and full Calendly feature parity. AGPL-3.0 license.
- Easy!Appointments (3K+ GitHub stars) is built for service businesses -- multi-provider scheduling, customer management, and Google Calendar sync. Lightweight PHP stack. GPL-3.0 license.
- Rallly (4K+ GitHub stars) solves a different problem -- group scheduling polls. Participants vote on available times, and the organizer picks the winner. No accounts required. AGPL-3.0 license.
- Zcal is a free-as-in-beer Calendly alternative with unlimited booking links, but it is not open source and cannot be self-hosted. Include it in your evaluation if cost is your primary concern and data ownership is not.
- Self-hosting Cal.com costs roughly $600-1,200/year in infrastructure versus $1,920-3,840/year for Calendly Teams at just 20 users. The gap widens as your team grows.
Quick Comparison
| Tool | Best For | Self-Hostable | Team Scheduling | Integrations | Calendar Sync | License |
|---|---|---|---|---|---|---|
| Cal.com | Full Calendly replacement | Yes (Docker) | Round-robin, collective, group | 70+ (Zoom, Meet, Stripe, Zapier) | Google, Outlook, Apple | AGPL-3.0 |
| Easy!Appointments | Service businesses | Yes (PHP + MySQL) | Multi-provider | Google Calendar, webhooks | Google Calendar | GPL-3.0 |
| Rallly | Group meeting polls | Yes (Docker) | Poll-based consensus | None (standalone) | No | AGPL-3.0 |
| Zcal | Free personal scheduling | No (SaaS only) | Basic team pages | Zoom, Meet, Teams | Google, Outlook | Proprietary |
Cal.com -- Best Overall Calendly Alternative
Cal.com (formerly Calendso) is the most direct open source competitor to Calendly. With 39,000+ GitHub stars, enterprise customers, and near-complete feature parity, it's the tool most teams should evaluate first. The platform covers everything from simple "book a meeting" links to complex multi-team routing workflows.
Cal.com is backed by venture funding and maintains both a hosted SaaS (cal.com) and a fully self-hostable open source edition under the AGPL-3.0 license.
Key Features
- Event types -- one-on-one, group, collective (all must attend), and round-robin (auto-assign to available team members) scheduling
- Routing forms -- ask screening questions and route bookers to the correct event type or team member based on their answers
- Workflows -- automated email and SMS reminders, pre-meeting questionnaires, and post-meeting surveys with conditional logic
- 70+ integrations -- Google Calendar, Outlook, Apple Calendar, Zoom, Google Meet, Stripe payments, HubSpot, Salesforce, Zapier, and more
- Cal.ai -- AI-powered scheduling from email. Forward a scheduling request and Cal.ai handles it
- Booking embeds -- inline, popup, and floating button embeds for your website
- Native video -- built-in video conferencing (Cal Video) with no call time limits and up to 300 participants
- API -- full REST API for building custom scheduling workflows
Pricing
- Self-hosted -- Free, all core features, AGPL-3.0 license
- Starter (hosted) -- Free, limited features
- Team -- $15/user/month, adds round-robin, routing forms, managed event types, workflow automation, and removes Cal.com branding
- Organization -- Custom pricing, adds SAML SSO, directory sync, and advanced admin controls
Self-Hosting Requirements
Cal.com is a Next.js application with a moderate deployment footprint:
- Cal.com app -- Next.js application (Docker image or build from source)
- PostgreSQL -- primary database
- Prisma -- ORM, handles migrations
- Optional: Redis (required for API v2), SMTP server for email notifications
Docker Compose gets you running, but note that Cal.com, Inc. does not provide official Docker support -- the Docker configuration is community-maintained. You will need to generate values for NEXTAUTH_SECRET and CALENDSO_ENCRYPTION_KEY and configure calendar provider OAuth credentials (Google, Microsoft) yourself. Minimum recommended: 2 vCPU, 4GB RAM.
Best For
Teams migrating from Calendly who want the closest feature match. Sales teams that need round-robin lead routing. Organizations that require full data sovereignty over scheduling data. Developers building scheduling into their own products via the API.
Limitations
Self-hosting documentation has gaps, and the Docker setup is community-driven rather than officially supported. Some advanced features (managed event types, certain workflow automations) require the paid Team plan even when self-hosting. The AGPL license requires you to open-source any modifications if you distribute the software -- fine for internal use, but a consideration for SaaS builders. Build times can be slow due to the large Next.js monorepo.
Easy!Appointments -- Best for Service Businesses
Easy!Appointments is a different tool for a different problem. Where Cal.com replicates Calendly's "share a link, pick a time" model, Easy!Appointments is built for service organizations -- hair salons, medical clinics, consulting firms, repair shops -- where multiple service providers offer different services on individual schedules.
With 3,000+ GitHub stars and active development since 2013, it's a mature, stable platform that does one thing well.
Key Features
- Multi-provider scheduling -- add multiple staff members (service providers), each with their own working hours, breaks, and service assignments
- Service catalog -- define services with durations, prices, and which providers can deliver them
- Customer management -- maintain a customer database with booking history, contact details, and notes
- Booking widget -- embeddable booking form for your website
- Google Calendar sync -- two-way synchronization with Google Calendar for each provider
- Email notifications -- automated confirmation and reminder emails
- Multi-language -- supports 25+ languages out of the box
- Admin dashboard -- calendar views, appointment management, and reporting
Pricing
- Self-hosted -- Free, GPL-3.0 license. No paid tiers, no premium features locked behind a paywall
Self-Hosting Requirements
Easy!Appointments has the lightest deployment requirements of any tool on this list:
- Apache or Nginx -- standard web server
- PHP 8.2+ -- the application runtime
- MySQL/MariaDB -- database
That's it. No Redis, no message queues, no Node.js build step. This runs on any $5/month shared hosting plan. Docker images are available if you prefer containerized deployment. The entire application is a PHP codebase -- deploy it like WordPress.
Best For
Service businesses with multiple providers and appointment-based workflows. Small businesses that want simple, reliable booking without the complexity of a full scheduling platform. Organizations already running PHP/MySQL stacks.
Limitations
No round-robin or team scheduling in the Calendly sense. No payment processing. No Zoom/Meet integration -- it schedules appointments, not video meetings. The UI is functional but dated compared to Cal.com or Calendly. No Outlook/Microsoft 365 calendar sync (Google Calendar only). The integration ecosystem is minimal -- no Zapier, no CRM connectors, no webhook automation beyond basic triggers.
Rallly -- Best for Meeting Polls
Rallly solves a specific scheduling problem that neither Calendly nor Cal.com addresses well: finding a time that works for a group. Instead of sharing availability slots, you propose dates and times, participants vote on what works, and you pick the winner. Think Doodle, but open source and without the ads.
With 4,000+ GitHub stars and active development, Rallly is a focused, polished tool.
Key Features
- Poll-based scheduling -- propose multiple dates/times, share a link, and let participants vote
- No account required -- participants vote without signing up. Zero friction
- Automatic time zones -- times are converted to each participant's local zone
- Large group support -- handles 10+ participants cleanly, with a clear visual grid showing availability overlap
- Comments -- participants can add notes explaining their preferences or constraints
- Finalize and notify -- lock in the chosen time and notify all participants
Pricing
- Self-hosted -- Free, AGPL-3.0 license
- Rallly hosted -- Free tier available, paid plans for additional features
Self-Hosting Requirements
Rallly is a modern Next.js application with a clean Docker deployment:
- Rallly app -- Next.js application (official Docker image)
- PostgreSQL -- database (via Prisma ORM)
- SMTP server -- for sending email notifications (required)
Docker Compose with two services (app + database) plus SMTP credentials. x86-64 architecture only -- arm64 support has been suspended. Minimal resource requirements -- 1 vCPU, 1GB RAM is sufficient.
Best For
Teams that need to coordinate meeting times across many participants. Event organizers. Anyone frustrated with the 20-email chain of "does Tuesday work for everyone?" Complement it with Cal.com -- use Rallly to find the time, Cal.com to manage the booking.
Limitations
Rallly is not a Calendly replacement -- it's a Doodle replacement. No booking pages, no calendar sync, no automated event creation, no integrations. It does one thing (meeting polls) and does it well, but it won't replace your scheduling infrastructure.
Zcal -- Free but Not Open Source
Zcal deserves mention because it solves the cost problem without solving the ownership problem. It's a free scheduling tool with unlimited booking links, calendar connections, and integrations with Zoom, Google Meet, and Microsoft Teams. For individuals and small teams, it genuinely replaces Calendly at zero cost.
Key Features
- Unlimited event types -- no artificial limits on booking links
- Unlimited calendar connections -- sync as many calendars as you need
- Team scheduling -- coordinate required and optional hosts
- Video integrations -- Google Meet, Zoom, Microsoft Teams
- Custom form fields -- ask invitees questions before booking
- Booking limits -- cap daily/weekly bookings and add buffer times
Why It's on This List (and Why It's Last)
Zcal is free and functional, making it a legitimate Calendly alternative for cost-conscious users. But it is proprietary SaaS -- no source code, no self-hosting, no data sovereignty. Your scheduling data lives on Zcal's servers under Zcal's terms.
If your primary concern is "I don't want to pay Calendly's prices" and you're comfortable with a hosted service, Zcal works. If you care about data ownership, long-term vendor independence, or customization, look at Cal.com instead.
Best For
Individuals and freelancers who want free scheduling without self-hosting. Teams evaluating whether they need a scheduling tool before committing to self-hosting infrastructure.
Limitations
Not open source. Cannot be self-hosted. Dependent on Zcal's continued operation and pricing decisions -- the same vendor lock-in risk as Calendly, just at a lower price point today.
How to Choose
"I want the closest thing to Calendly" -- Cal.com. Same booking page model, similar feature set, and the most active open source scheduling community. Self-host it or use the managed service.
"I run a service business with multiple staff" -- Easy!Appointments. Multi-provider scheduling, service catalogs, and customer management built for appointment-based businesses. Dead simple to deploy.
"I need to find a time that works for a group" -- Rallly. Poll-based scheduling that eliminates the back-and-forth. Not a Calendly replacement, but a perfect complement to one.
"I just want free scheduling, I don't care about self-hosting" -- Zcal. Free, functional, and the fastest path from Calendly to not paying. Accept the trade-off on data ownership.
"I need the full stack" -- Cal.com + Rallly. Cal.com handles booking pages and team scheduling. Rallly handles group availability polls. Together they cover everything Calendly does and more.
Pricing: Calendly vs Self-Hosted
Calendly Costs by Team Size (Annual Billing)
| Team Size | Standard ($10/user/mo) | Teams ($16/user/mo) |
|---|---|---|
| 5 users | $600/yr | $960/yr |
| 20 users | $2,400/yr | $3,840/yr |
| 50 users | $6,000/yr | $9,600/yr |
| 100 users | $12,000/yr | $19,200/yr |
Self-Hosting Cal.com (All Team Sizes)
| Cost Component | Annual Estimate |
|---|---|
| VPS (2 vCPU, 4GB RAM) | $240-$480 |
| PostgreSQL (managed or self-hosted) | $0-$300 |
| Admin time (2-3 hrs/month at $75/hr) | $1,800-$2,700 |
| Domain + SSL | $12-$20 |
| SMTP service (Mailgun, SES) | $0-$120 |
| Total (any team size) | $2,052-$3,620 |
At 5 users, self-hosting costs more than Calendly Standard when you include admin time. At 20 users, you break even with Calendly Teams. At 50+ users, the savings are clear -- $3,000 to $6,000 per year compared to Calendly Teams.
If you already have DevOps staff, the effective cost drops to under $600/year because the admin overhead is absorbed into existing workloads. The server itself handles hundreds of users without scaling.
Easy!Appointments: Even Cheaper
Easy!Appointments runs on shared hosting. If you already have a PHP/MySQL server (most web hosts include this), the marginal cost is effectively zero. Even dedicated hosting runs $60-$120/year. There is no team-size scaling cost at all.
Methodology
We evaluated these tools based on:
- Feature parity with Calendly -- booking pages, event types, calendar sync, team scheduling, integrations, workflows, and embeds.
- Self-hosting viability -- deployment complexity, documentation quality, resource requirements, and ongoing maintenance burden.
- Community and ecosystem -- GitHub activity, star count, contributor base, and integration availability as of March 2026.
- Total cost of ownership -- server requirements, admin overhead, and optional paid tiers compared to Calendly pricing at various team sizes.
- Honest limitations -- where each tool falls short relative to Calendly's polished, mature platform.
We did not accept payment or sponsorship from any project listed. Tools were evaluated via self-hosted deployments, public instances, and documentation review.
Find Your Alternative
For most teams, Cal.com is the right starting point -- it's the most Calendly-like experience with the strongest community and the broadest feature set. If your use case is service-business booking or group scheduling polls, Easy!Appointments and Rallly are better fits for those specific workflows.
Browse all Calendly alternatives on OSSAlt to see detailed feature comparisons, deployment guides, and community reviews -- and find the right scheduling tool for your team.