Slack is a team communication application providing services such as real-time messaging, archiving and search for modern teams. It offers one-on-one messaging, private groups, persistent chat rooms and direct messaging as well as group chats organized by topic. All content inside Slack is searchable from one search box and it integrates with a number of third-party services, including Google Docs, Dropbox, Heroku, Crashlytics, GitHub and Zendesk.

Company Growth (employees)
San Francisco, US
Size (employees)
933 (est)+17%
Slack was founded in 2009 and is headquartered in San Francisco, US

Key People at Slack

Stewart Butterfield

Stewart Butterfield

Co-Founder / CEO
Cal Henderson

Cal Henderson

Robert Frati

Robert Frati

Vice President of Sales
April Underwood

April Underwood

VP of Product
Brandon Zell

Brandon Zell

Corporate Controller
Sarah Friar

Sarah Friar

Independent Board Member
Allen Shim

Allen Shim

SVP of Finance & Operations

Slack Office Locations

Slack has offices in San Francisco, Dublin, London, Vancouver and in 4 other locations
San Francisco, US (HQ)
155 5th Street 6th Floor
Show all (8)

Slack Data and Metrics

Summary Metrics

Slack's latest funding round in July 2017 was reported to be $250 m. In total, Slack has raised $790 m. Slack's latest valuation is reported to be $5 b.

Slack Financial Metrics

Slack's revenue was reported to be $64 m in 2016

Revenue (Y, 2016)

64 m

Market valuation

5 b
USDY, 2016


64 m
USDY, 2016


118.8 k

Slack Operating Metrics

Slack's Users was reported to be 4 m in 2016. Slack's Daily Active Users was reported to be 5 m in Mar, 2017. Slack's Enterprise Customers was reported to be 38 k in Apr, 2017. Slack's Accounts was reported to be 1.5 m in Mar, 2017
Y, 2016Mar, 2017Apr, 2017

Daily Active Users

4 m5 m

Paying Users

1.25 m


4 m


1.5 m

Enterprise Customers

38 k

Slack Acquisitions / Subsidiaries

Acquired CompanyDateDeal Size
ScreenheroJanuary 28, 2015
SpacesSeptember 26, 2014

Traffic Overview of Slack

Slack Online and Social Media Presence

Slack News and Updates

Slacktivist thank you: 'SNL' has a song for people who tweet from the toilet

Give yourselves a pat on the back. You are the heroes.  Here's to the people who post and share stories about serious issues on Facebook, and then do nothing else to help.  Saturday Night Live paid tribute to you in a music video featuring Louis C.K.  Because tweeting about a humanitarian cr…

Don't look down: These slacklining photos will give you full-blown vertigo

Scared of heights? We apologise for what you're about to see.  But the video footage and imagery captured by this Tasmanian photographer and videographer is too awe-inspiring to not share. Simon Bischoff is a Hobart-based nature-lover who works under the name Video Compass, and the footage h…

ProBeat: Slack is screwed

OPINION: Slack’s problem just got a lot worse. Not only did the full-page New York Times ad fail to stop the upcoming launch of Microsoft Teams next week on March 14, but now Google is entering the fray with Hangouts Chat in private beta. For the millions of G Suite and Office 365 users, Slack will …

Google is Slackifying Hangouts

Google is making massive changes to Hangouts. After what feels like years without significant updates, the company announced a total overhaul of the messaging app. In an effort to make Hangouts more business-friendly, Google is splitting the service into two separate apps: Hangouts Meet, a video…

Reporters Love Chatrooms But Worry Security Is Slacking

Slack and other virtual newsrooms have some reporters concerned about privacy in an era of embattled journalism that relies on discretion. Slack and other virtual newsrooms have some reporters concerned about privacy in an era of embattled journalism that relies on discretion.L…

Step inside Slack's light-drenched New York City office

Slack is one of the most closely watched startups in Silicon Valley, and now it has a home base in New York, too.  The three-year-old chat app maker boasts 4 million daily users, from employees at media companies like Business Insider, to workers at companies like IBM, who u…
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Slack Company Life and Culture

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