Cal.com

Cal.com was founded in 2021 by Peer Richelsen and Bailey Pumfleet as Calendso, launched as an alternative to Calendly; later that year the company acquired the cal.com domain and took that name. The company says Peer started Calendso because every scheduling tool at the time was closed and none could be embedded.⁠[1]

Five months after its first launch on Product HuntProduct HuntProduct Hunt is a product-discovery and launch community founded by Ryan Hoover in 2013 and operated by Product Hunt, Inc. Makers present new products, while users vote, comment and review them and discover tools through categories, forums and AI search. AngelList announced its acquisition in 2016; as of November 2026, its official website lists Rajiv Ayyangar as CEO.Open the full entry, Calendso announced its rebrand to Cal.com and released its first v1.0 release candidate. The company said the side project, begun as an open-source alternative to Calendly, was serving thousands of customers and hundreds of companies, and that On DeckOn DeckOn Deck is a founder community and program company launched in June 2019 by David Booth and Erik Torenberg, connecting founders with peers, capital and advice; its first program was the Founders Fellowship (ODF). It raised a $20 million Series A led by Founders Fund in March 2021 and cut staff twice in 2022 as it narrowed its business.Open the full entry was the first company to launch a product on its open core.⁠[2]

Cal.com announced a $7.4 million seed round led by Joseph Jacks of OSS Capital, with participation from Naval RavikantNaval RavikantNaval Ravikant is an entrepreneur and angel investor and a co-founder of AngelList. Early on he co-founded the review site Epinions; he and Babak Nivi later grew AngelList out of the startup-fundraising blog Venture Hacks, and he co-founded the cryptocurrency hedge fund MetaStable Capital and Spearhead, which backs founders to make angel investments. His views on startups and life were compiled into the book The Almanack of Naval Ravikant.Open the full entry, Chad Hurley, Balaji S. SrinivasanBalaji SrinivasanBalaji Srinivasan is an entrepreneur, investor and the author of The Network State, the founder of Network School, and a former chief technology officer of Coinbase and general partner at Andreessen Horowitz. He co-founded Counsyl and 21, along with its successor product Earn.com, was involved in projects such as Coin Center, and has backed companies such as fomo as an angel investor.Open the full entry, Neha Narkhede, Eliot HorowitzEliot HorowitzEliot Horowitz is a software engineer and entrepreneur who co-founded the database company MongoDB (originally 10gen) with Dwight Merriman and Kevin Ryan in 2007 and served as its chief technology officer from 2008 to 2020; in 2020 he set out to build the robotics software platform company Viam, which he leads as chief executive.Open the full entry, Guillermo RauchGuillermo RauchGuillermo Rauch is a software developer, entrepreneur and angel investor, and the founder and CEO of Vercel. Originally from Argentina, he was active early in the JavaScript open-source community, co-founded LearnBoost and Cloudup, and worked on projects including Socket.IO, Mongoose and Next.js. He published Smashing Node.js: JavaScript Everywhere in 2012 and in 2015 founded ZEIT, the company later renamed Vercel.Open the full entry, Paul Copplestone, On Deck and others. Domain Name Wire covered the round on January 6, 2022, linking the company’s growth to its move to the cal.com domain.⁠[3][4]

In an interview recorded in May 2022, Bailey Pumfleet said Cal.com then had about $15,000 in monthly recurring revenue and 25,000 to 30,000 total users, with engineers making up about 90% of the team; the interview page gives the company’s Series A that year as $25 million.⁠[5]

On April 14, 2026, Bailey Pumfleet announced that after five years as an open-source company Cal.com was going closed source. He wrote that AI can be pointed at an open-source codebase to scan it systematically for vulnerabilities, that being open source was increasingly like giving attackers the blueprints to the vault, and that protecting customer data had to come first; an open version for hobbyists would continue as Cal.diy.⁠[6]

Cal.com describes itself as a scheduling platform for individuals, teams and the products built on it, offering booking links, routing, workflows, Cal Video and Cal.ai on cal.com or embedded in other apps; its mission is to connect a billion people by 2031 through calendar scheduling. Its team works remotely across Europe, the Americas and Asia; Peer leads product and engineering, and Bailey, as chief executive, leads go-to-market, marketing and sales.⁠[1]

Cal.com: Official website: https://cal.com/ (opens in a new window).⁠[1]

X: https://x.com/calcom (opens in a new window).⁠[1]

LinkedInLinkedInLinkedIn is a social networking platform for professionals. It was founded in 2002 by Reid Hoffman and others, launched in 2003, and listed on the New York Stock Exchange in 2011; after Microsoft acquired it for approximately $26.2 billion in 2016, it became a wholly owned Microsoft subsidiary. Its revenue comes from membership subscriptions, advertising, and recruitment solutions.Open the full entry: https://www.linkedin.com/company/cal-com (opens in a new window).⁠[1]

YouTubeYouTubeYouTube is Google’s video-sharing and creator platform, founded in 2005 by Steve Chen, Chad Hurley, and Jawed Karim and acquired by Google in 2006. Built around video uploading, viewing, and creator earnings, the platform has developed Shorts, YouTube Music, Premium, YouTube TV, and products for children, and is headquartered in San Bruno, California, United States.Open the full entry: https://www.youtube.com/@calcominc (opens in a new window).⁠[1]

GitHub: https://github.com/calcom (opens in a new window).⁠[1]