Software Alternatives, Accelerators & Startups

Cal.com VS Flagsmith

Compare Cal.com VS Flagsmith and see what are their differences

Note: These products don't have any matching categories. If you think this is a mistake, please edit the details of one of the products and suggest appropriate categories.

Cal.com logo Cal.com

Cal.com (formerly Calendso) is the open source Calendly alternative.

Flagsmith logo Flagsmith

Flagsmith lets you manage feature flags and remote config across web, mobile and server side applications. Deliver true Continuous Integration. Get builds out faster. Control who has access to new features. We're Open Source.
  • Cal.com Landing page
    Landing page //
    2023-10-08
  • Flagsmith Landing page
    Landing page //
    2021-10-23

Cal.com features and specs

  • Customizable
    Cal.com allows extensive customization to fit various branding and scheduling needs, which makes it adaptable for different types of users including businesses and individuals.
  • Open-source
    Being an open-source platform, Cal.com provides the flexibility for developers to modify and extend the software as per their specific needs, fostering a collaborative development environment.
  • Integrations
    Cal.com offers a wide range of integrations with other software tools like Google Calendar, Microsoft Outlook, and Zoom, enhancing its functionality and making it easier to fit into existing workflows.
  • User-friendly Interface
    Cal.com has an intuitive and clean interface that makes it easy for users of all technical skill levels to set up and manage their scheduling.
  • Privacy-focused
    Cal.com emphasizes data privacy, ensuring user information is handled securely, which is crucial for users who need to comply with regulations like GDPR.

Possible disadvantages of Cal.com

  • Learning Curve
    Although it is highly customizable, the plethora of options and features may result in a steeper learning curve for new users who are not familiar with such scheduling tools.
  • Limited Free Version
    The free version of Cal.com comes with limitations that may not be sufficient for growing businesses or advanced users who require more comprehensive features.
  • Dependency on Integrations
    Cal.com's effectiveness heavily depends on its integrations. Without these integrations, some users might find the tool less useful or incomplete, especially if their primary tools are not supported.
  • Support
    While open-source has many benefits, it may also mean that immediate, personalized support could be limited compared to fully commercial solutions. This might pose a challenge for users needing quick resolutions.
  • Performance
    As an open-source platform, the performance might vary depending on how it is hosted and managed. Suboptimal configurations could lead to slower performance or downtimes.

Flagsmith features and specs

  • Feature Flags
  • Remote Config
  • A/B/X Testing & Optimization
  • Organization Management
  • Integrations

Analysis of Cal.com

Overall verdict

  • Cal.com is generally considered a good option for scheduling and calendar management.

Why this product is good

  • Cal.com is praised for its open-source nature, allowing for greater customization and integration flexibility. It offers a user-friendly interface and supports various calendar integrations, making it a versatile tool for individuals and businesses alike.

Recommended for

  • Freelancers who need a simple yet effective scheduling tool.
  • Small businesses looking for a customizable scheduling solution.
  • Developers who appreciate open-source software and need a tool they can modify.
  • Businesses seeking a platform that can integrate with existing tools and workflows.

Analysis of Flagsmith

Overall verdict

  • Flagsmith is a good choice for teams looking for a reliable and customizable feature management tool. Its open-source nature and comprehensive feature set make it suitable for both small startups and large enterprises. However, the best fit will depend on your specific needs, such as the size of your team, required integrations, and budget.

Why this product is good

  • Flagsmith is widely appreciated for its simplicity, ease of integration, and robust feature flagging capabilities that help teams manage feature rollouts, AB tests, and configuration toggling. It is open-source, which allows users to benefit from a collaborative community and flexibility in customization. Furthermore, its scalable infrastructure supports modern development workflows and ensures smooth performance.

Recommended for

  • Development teams seeking an open-source feature flagging solution
  • Organizations that need flexible feature management across various environments
  • Companies looking for a solution that supports rapid experimentation and testing
  • Teams aiming for granular control over feature rollout and user segmentation

Cal.com videos

What can you do with Cal? | Cal.com Version 1.1 Launch | 10 new languages

More videos:

  • Review - Cal.com Version 1.0 Launch Event

Flagsmith videos

No Flagsmith videos yet. You could help us improve this page by suggesting one.

Add video

Category Popularity

0-100% (relative to Cal.com and Flagsmith)
Appointments and Scheduling
Feature Flags
0 0%
100% 100
Calendar And Scheduling
100 100%
0% 0
Developer Tools
0 0%
100% 100

User comments

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Reviews

These are some of the external sources and on-site user reviews we've used to compare Cal.com and Flagsmith

Cal.com Reviews

Acuity Scheduling alternatives for businesses outgrowing it
The honest read: if you're leaving Acuity because your business outgrew simple scheduling โ€” you need deposits, add-ons, multiple staff and locations, and ideally a booking site you own โ€” Opencals is built for exactly that transition, and pay-as-you-go means it costs nothing until you're earning. If you're leaving for a narrower reason, match it precisely: SimplyBook.me for...
Source: opencals.com
I've poked around a while ago at some Calendly alternatives (specifically was lo... | Hacker News
I tried using https://cal.com for a bit but ended up just switching over to https://zcal.co and it has been great so far. All these other scheduling tools end up trying to do too much and always seem to end up a bit clunky and charge absurd amounts for it

Flagsmith Reviews

The 8 best free and open-source feature flag services
BlogBackSign inBlogThe 8 best free and open-source feature flag servicesPosted byThe best open-source feature flag tools1. PostHogWhat is PostHog?Supported librariesHow much does it cost?2. UnleashWhat is Unleash?Supported SDKsHow much does it cost?3. GrowthBookWhat is GrowthBook?Supported SDKsHow much does it cost?4. FlagsmithWhat is Flagsmith?Supported SDKsHow much does it...
Source: posthog.com

Social recommendations and mentions

Based on our record, Cal.com should be more popular than Flagsmith. It has been mentiond 60 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

Cal.com mentions (60)

  • "You Wouldnโ€™t Steal a DIV": How I Built My Portfolio
    Then for the component library, I was really into coss ui. I stumbled upon it randomly one day and loved it so much. My Nathan's AI project already had a UI heavily inspired by cal.com: send button, message suggestions... So when I saw they had a shadcn/ui library with that kind of style, it was perfect for what I needed. - Source: dev.to / 4 months ago
  • AI Almost Sold Me a Subscription I Didn't Need
    I keep coming back to what would have happened if I didn't have a strong technical understanding of how calendar technology works โ€” the difference between local and cloud calendars, what an ICS feed is, why enterprise auth blocks third-party integrations. If this was many years ago before I gained all this experience, I would have stopped at the first confident answer from my search tool, installed one of those... - Source: dev.to / 5 months ago
  • Introducing Quackback: Open-Source Feedback Platform with a Built-in MCP Server
    Plausible brought open source to web analytics. Cal.com did it for scheduling. Formbricks did it for surveys. PostHog did it for product analytics. Quackback does it for feedback collection. - Source: dev.to / 5 months ago
  • ๐Ÿค Learn Front-End by Doing: Contribute to Cal.com's Open Source...๐Ÿš€
    In this tutorial, we'll be focusing on Cal.com:. - Source: dev.to / 12 months ago
  • 5 Side Project Ideas for Developers to Monetize as Micro-SaaS in 2025
    Take Cal.com (https://cal.com/), formerly known as Calendso. It started as an open source alternative to Calendly which offers a free, self-hostable version for users. - Source: dev.to / over 1 year ago
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Flagsmith mentions (13)

  • Why use Open Source Feature Flags?
    Considering all these points, the team at Flagsmith has developed a feature flag management platform Flagsmith and made it open source. The core functionality is open and you can check out the GitHub repository here. I have utilized and authored several blogs discussing their excellent offerings and strategies. - Source: dev.to / about 2 years ago
  • free-for.dev
    Flagsmith - Release features with confidence; manage feature flags across web, mobile, and server side applications. Use our hosted API, deploy to your own private cloud, or run on-premise. - Source: dev.to / over 3 years ago
  • Which startups are made using Django?
    Flagsmith is written in Django and is open source as well: https://flagsmith.com. Source: about 4 years ago
  • The actual infrastructure costs of running SaaS at scale (billions of requests/month)
    Before we dive in, one important call-out: We provide our feature management product to customers in three ways depending on how they want to have it managed: Fully Managed SaaS API, Fully Managed Private Cloud SaaS API and Self-Hosted. The infrastructure costs that we are sharing is for our customers that leverage our Fully Managed SaaS API offering (try it free: https://flagsmith.com/) which represents a portion... - Source: dev.to / about 4 years ago
  • The Story Behind Our Open Source Ecommerce Platform with +9,000 GH stars in 6 months
    On March 15th, Sebastian Rindom, the CEO & Co-founder of Medusa, did an interview with Flagsmith where he talked about how Medusa started, why create a headless commerce solution, why make it open-source, and more. - Source: dev.to / over 4 years ago
View more

What are some alternatives?

When comparing Cal.com and Flagsmith, you can also consider the following products

Calendly - Say goodbye to phone and email tag for finding the perfect meeting time with Calendly. It's 100% free, super easy to use and you'll love our customer service.

LaunchDarkly - LaunchDarkly is a powerful development tool which allows software developers to roll out updates and new features.

TidyCal - Optimize your schedule with custom booking pages and calendar integrations

ConfigCat - ConfigCat is a developer-centric feature flag service with unlimited team size, awesome support, and a reasonable price tag.

Acuity Scheduling - Automate your client bookings, cancellations, reminders & payments using the worlds friendliest online scheduling software.

Unleash - Unleash is an open-source feature management platform. We are private, secure, and ready for the most complex setups out of the box.