Cal Henderson
San Francisco, United States
The gaming engineer who transformed work - turning a simple game fix into Slack, the $27bn platform that has revolutionised workplace collaboration worldwide.
Interests
Impact
200K+
Customers globally
150+
Countries Operated In
$27.7B
Exit value
2500+
People employed
1B+
Funding raised
13+
Early stage investments
$26B+
Recent valuation
Born in Bedfordshire
Callum James Henderson-Begg was born on 17th January 1981 in Bedfordshire, England. He would later credit his early interest in computers and internet culture to growing up in a household that encouraged curiosity and self-direction.
World Map
Bedford, UK
GB
Cal was born in Bedfordshire in 1981 and later attended Sharnbrook Upper School, his early roots, where coding curiosity and internet humour first found fertile ground.
Press
TechCrunch
Slack’s Cal Henderson and Sir Richard Branson back firstminute capital’s third fund
12th June 2023
The Telegraph
‘Why would anyone want to go back to the office?’, says Slack’s Cal...
12th December 2020
Business Insider
How Slack's Engineering Team Is Adapting to Remote Work Long-Term
5th October 2020
WIRED
The pandemic changed how everyone uses Slack
28th August 2020
Business Insider
Here's who's getting rich now that Slack is a public company worth over $20 billion
20th June 2019
Business Insider
The Latest: Slack Becomes Latest Tech Company to Go Public
20th June 2019
Business Insider
A Silicon Valley CTO says the workplace skills he'll make sure his children learn have nothing to do with tech
5th December 2018
Forbes
How To Boss It Like: Cal Henderson, CTO At Slack
13th April 2018
TechCrunch
How Slack uses a raccoon to keep distractions on Slack at bay
4th December 2017
Media
Career Milestones
Slack Technologies, Inc
A productivity platform for customer companies that improves performance by making search and knowledge sharing seamless, and keeping teams connected and engaged.
2009 – 2024
Flickr
The world's largest photography community that provides users with a safe and inclusive platform for sharing and connecting through photos and videos
2003 – 2009
EMAP
A content, subscription and networking business that connects influential people and organisations to a high-value network of decision-makers, data and ideas.
2001 – 2004
Early Stage Investments
A strong core philosophy is that we should finish things to a reasonable extent, then get them out there. That's always an internal struggle between perfection and shipping things on time or shipping things quickly.
Philanthropy
Birmingham City University
This university focuses on practice-led, knowledge-based learning, providing access to cutting-edge facilities and real-world experience. Cal made a donation to this university, his alma mater in 2024
$500k donated
150 scholarships and bursaries
Supported disadvantaged groups2024
Birmingham, England
Founders Brands Limited
180 Strand, 2 Arundel Street, London,
United Kingdom, WC2R 3DA
Company number: 15716753
VAT number: 487 5152 58
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