A Complete Guide to Cal.com: The Open-Source Scheduling Powerhouse – Prabhat Shrivastava

A Complete Guide to Cal.com: The Open-Source Scheduling Powerhouse

In today’s fast-paced world, the simple act of scheduling a meeting can feel like a game of digital ping-pong. “What time works for you?” followed by a dozen back-and-forth emails. Thankfully, a new generation of scheduling tools has emerged to put an end to this. While Calendly has long been the market leader, a powerful, open-source competitor is rapidly changing the game: Cal.com.¹

This guide will walk you through everything you need to know about Cal.com, from setting up your first event to integrating it with your favorite apps, and even a statistical look at how it stacks up against the competition.

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What is Cal.com?

At its core, Cal.com is an open-source scheduling platform designed to make booking meetings seamless and efficient.² It’s built on a philosophy of giving users more control, transparency, and flexibility.³ Unlike proprietary tools, Cal.com’s source code is publicly available on GitHub, allowing developers to customize the platform to fit unique needs.⁴ This “open-first” approach has garnered a strong community and attracted significant funding, positioning it as a serious contender in the scheduling space.⁵

Whether you’re a freelancer, a small business, or a large enterprise, Cal.com simplifies the process of finding a time to meet. You simply share a link, and your invitees can book a time that works for them, automatically syncing with your calendar.⁶

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How to Get Started with Cal.com

Getting your Cal.com account up and running is a straightforward process. The platform is designed to be intuitive, ensuring you can start booking meetings in just a few minutes.

Step 1: Sign Up and Connect Your Calendar

The first step is to create an account on Cal.com.⁷ Once you’re in, the platform will guide you to connect your existing calendar.

• Connect Your Calendar: Cal.com seamlessly integrates with all major calendar services. You can connect your Google Calendar, Microsoft 365, Outlook, iCloud Calendar, and even less common ones like Zoho Calendar and Zimbra. This is a crucial step, as it allows Cal.com to see your existing appointments and block out unavailable times, preventing double bookings.

Step 2: Create Your First Event Type

An “event type” is the template for a meeting you want to offer.⁸ You can have multiple event types for different purposes, such as a “15-Minute Discovery Call,” a “30-Minute Demo,” or a “60-Minute Consulting Session.”⁹

• Name Your Event: Give your event a clear and concise name.
• Set the Duration: Define how long the meeting will last.¹⁰
• Add a Location: Choose your meeting location.¹¹ Cal.com offers a variety of options including video conferencing tools (Zoom, Google Meet, Microsoft Teams), phone calls, or a physical address.¹²
• Set Your Availability: This is where you define when you are available for this specific event type.¹³ You can set a fixed schedule (e.g., Monday-Friday, 9 a.m. to 5 p.m.) or customize it for specific days.¹⁴ You can also add a buffer time between meetings to give yourself a break.
• Customize Your Booking Page: You can personalize your booking page with a logo, a description, and questions for your invitees to answer when they book a slot.¹⁵

Step 3: Share Your Link

Once your event type is created, Cal.com generates a unique booking link for you.¹⁶ This link is your key to effortless scheduling.¹⁷

• Copy and Paste: You can paste your link into an email signature, a social media bio, or a text message.¹⁸
• Embed on Your Website: For businesses, a great way to use Cal.com is by embedding a booking widget directly onto your website. This allows clients to schedule a meeting with you without ever leaving your site.
• Use the Mobile App: Cal.com has a user-friendly mobile app that allows you to manage your schedule, confirm bookings, and share your link on the go.

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Seamless Integrations: The Cal.com Ecosystem

One of Cal.com’s greatest strengths is its deep and wide-ranging list of integrations. The platform goes beyond just calendars, connecting with a vast ecosystem of apps to automate workflows and supercharge your productivity.¹⁹

Calendar & Video Conferencing

• Google Calendar & Microsoft 365: The foundation of Cal.com. These integrations are essential for synchronizing your availability and adding new bookings directly to your primary calendar.
• Zoom, Google Meet, Microsoft Teams: Automatically generates unique video conference links for every meeting booked.²⁰ No more manually creating and sharing links.
• Discord & Element Call: For communities and teams that use these platforms, Cal.com offers seamless integration to schedule meetings directly within your preferred communication tools.

CRM & Marketing Automation

• HubSpot & Salesforce: When a meeting is booked, Cal.com can automatically create or update a contact record in your CRM. This ensures your sales and marketing teams have the most up-to-date information.
• ActiveCampaign & Mailchimp: Automatically add new bookings as subscribers to your mailing lists or trigger marketing automation workflows.²¹
• Airtable: Use Airtable as a custom database to store booking information and build custom dashboards.

Productivity & Collaboration

• Slack & Telegram: Get instant notifications in your team chat when a new meeting is booked, rescheduled, or canceled.²²
• Notion & Todoist: Automatically create tasks or to-do list items in your favorite productivity tools whenever a new event is scheduled.
• Zapier & Pabbly Connect: These integration platforms are the ultimate workflow automation tools. They allow you to connect Cal.com with thousands of other apps, enabling you to build custom, code-free workflows.²³ For example, you can create a Google Sheet row for every new booking or send a custom email to an attendee.²⁴

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Cal.com vs. the Competition: A Statistical Perspective

While providing exact, real-time market share statistics for a blog post can be challenging due to the private nature of many companies, we can analyze publicly available data and reported metrics to draw a clear comparison.

💰 Funding and Valuation

• Cal.com: As of its latest public funding rounds, Cal.com has raised $32.4 million in funding.²⁵ Its investors include notable names like Alexis Ohanian’s Seven Seven Six.²⁶ This shows significant investor confidence in its open-source business model.
• Calendly: Calendly has a much larger valuation and funding history. It has raised over $350 million and was valued at $3 billion in its latest funding round. Calendly’s massive valuation reflects its decade-long head start and market dominance.

👨‍👩‍👧‍👦 User Base and Growth

• Calendly: Calendly’s user base is massive.²⁷ As of late 2023, it reported having over 20 million users across more than 100,000 businesses. This sheer volume of users gives it a powerful network effect, making it the default scheduling tool for many.
• Cal.com: As an open-source company, Cal.com’s exact user numbers are harder to pinpoint, as many users self-host their installations.²⁸ However, Cal.com’s open startup model allows us to look at some key metrics.²⁹ It has grown rapidly, and its unique value proposition is appealing to a different user segment, particularly developers and large enterprises who require deep customization and data sovereignty.³⁰

📈 The Value Proposition Showdown

This is where the numbers on the surface tell only part of the story. The real competition lies in their core business philosophies.

• Cal.com: The Open-Source Advantage
  • Cost: Cal.com’s free plan is significantly more generous, offering unlimited event types and calendar connections.³¹ Calendly’s free plan is restricted to one of each.³²
  • Flexibility & Customization: This is Cal.com’s ace.³³ Its open-source nature means organizations can self-host the platform, giving them complete control over their data and code.³⁴ For companies in regulated industries or with specific security requirements, this is a non-negotiable advantage.
• Calendly: The Proven Leader
  • Simplicity & Ease of Use: Calendly is renowned for its straightforward, no-frills user interface.³⁵ It is the go-to choice for individuals and small teams who want a simple, reliable solution with minimal setup.³⁶
  • Enterprise-Ready: With a massive user base and a decade of experience, Calendly has a robust enterprise-level solution with a clear, predictable pricing model for large corporations.

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Conclusion: Which One Should You Choose?

Ultimately, the choice between Cal.com and its competitors depends on your specific needs.

• Choose Calendly if you are a solo professional, a small business, or a non-technical team looking for a quick, simple, and reliable scheduling solution.³⁷ Its widespread adoption means many people are already familiar with it.
• Choose Cal.com if you are a developer, a technical organization, or a company with a high priority on data privacy, customization, and cost-effectiveness at scale.³⁸ Its open-source model gives you a level of control that proprietary software simply cannot match.³⁹ It’s a tool for those who want to build a better, more integrated scheduling infrastructure for their business, not just a simple booking link.⁴⁰

Sources

Sources & Further Reading:

1. On Cal.com’s Funding & Growth:

• Tracxn: Cal.com – 2025 Company Profile, Team, Funding & Competitors. Provides a detailed breakdown of Cal.com’s funding rounds, investors, and total capital raised. [Source]
• Clay: How Much Did Cal.com Raise? Funding & Key Investors. Offers an in-depth look at Cal.com’s funding journey and the strategic motivations behind each round. [Source]
• Cal.com Blog: How Cal.com Became Deel’s Go-To Tool for Scheduling. A case study providing specific user and performance metrics from one of Cal.com’s key clients, illustrating its real-world impact. [Source]

2. On Calendly’s Funding & User Base:

• Tracxn: Calendly – 2025 Company Profile, Team, Funding & Competitors. Details Calendly’s funding history, including its major Series B round and $3 billion valuation. [Source]
• SignHouse Blog: Calendly Revenue and Growth Statistics (2024). Provides statistics on Calendly’s revenue growth, market share, and user base. [Source]
• Calendly Website: The State of Meetings 2024. A commissioned report offering insights into meeting trends and productivity statistics, providing a broad context for the scheduling software market. [Source]

3. On the Cal.com vs. Calendly Comparison:

• YouCanBookMe Blog: Which Booking Tool is Better? Cal.com vs. Calendly 2025 Comparison. A competitor’s analysis that directly compares the features, pricing, and integrations of both platforms. [Source]
• Zeeg Blog: Calendly vs Cal.com: 2025 Comparison. Provides a high-level comparison of the two platforms’ core philosophies, user experience, and customization options. [Source]