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.
San Francisco, US
Size (employees)
1,265 (est)+3%
Slack was founded in 2009 and is headquartered in San Francisco, US
Report incorrect company information

Key People/Management at Slack

Stewart Butterfield

Stewart Butterfield

Co-Founder, CEO
Allen Shim

Allen Shim

Cal Henderson

Cal Henderson

Michael Lopp

Michael Lopp

VP Engineering
Ali Rayl

Ali Rayl

VP Customer Experience
Robert Frati

Robert Frati

VP Sales
Show more

Slack Office Locations

Slack has offices in New York, Melbourne, San Francisco, Tokyo and in 4 other locations
San Francisco, US (HQ)
500 Howard Street
New York, US
436 Lafayette Street
Melbourne, AU
551 Swanston St
Toronto, CA
171 John Street
Vancouver, CA
401, 1028 Hamilton Street
Dublin, IE
4th Floor, One Park Place
Show all (8)
Report incorrect company information

Slack Financials and Metrics

Summary Metrics

Slack's latest funding round in September 2017 was reported to be $250 m. In total, Slack has raised $854.4 m. Slack's latest valuation is reported to be $5.1 b.
Show all funding rounds

Slack Financials

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

Revenue (Y, 2016)

64 m

Market valuation

5.1 b
USDY, 2016E


64 m
USDY, 2016


118.8 k
Show all financial metrics

Slack Operating Metrics

Slack's Users was reported to be 4 m in Y, 2016. Slack's Daily Active Users was reported to be 8 m in May, 2018. Slack's Enterprise Customers was reported to be 500 k in May, 2018.
Jan, 2014Jul, 2014Oct, 2015Y, 2016Mar, 2017Apr, 2017Jun, 2017Sep, 2017Nov, 2017Feb, 2018May, 2018


12 k1.70 m4 m

Paying Users

38 k480 k1.25 m1.50 m2 m3 m

Daily Active Users

120 k4 m5 m5 m6 m8 m

Enterprise Customers

2 k90 k38 k50 k50 k50 k500 k
Show all operating metrics

Slack Acquisitions / Subsidiaries

Acquired CompanyDateDeal Size
Screenhero, Inc January 28, 2015
Spaces September 26, 2014
Report incorrect company information

Slack Online and Social Media Presence

Embed Graph
Report incorrect company information

Slack News and Updates

Collaboration Software Platform Samepage Secures Financing from Reflex Capital

CAMPBELL, Calif., June 20, 2018 /PRNewswire/ -- Samepage, an all-in-one team communication and collaboration platform, has secured seed financing from technology growth equity investor Reflex Capital. The financing will be used to expand the platform's functionality and global reach....

Four reasons why you should have a public API for your SaaS tool

In the competitive industry, SaaS vendors should ensure that the demand for their software continues by implementing APIs to their software.

Why You Should Slack Off to Get Some Work Done

One cautionary point: Pro-leisure science does not give permission to trance out on Twitter or graze Netflix endlessly.

Clique Named Finalist for Red Herring Top 100 North America Award

LOS ANGELES, June 15, 2018 /PRNewswire/ -- Clique, the company pioneering the global "Communications Platform as a Service" (CPaaS) revolution, announced today it has been selected as a finalist for Red Herring's Top 100 North America award. Issued annually by Red Herring, a global media...

A Silicon Valley VC firm just invested $10.5 million in an app that helps companies like Slack and Reddit make working parents' lives easier

Family and parenting app Cleo announced a $10.5 million investment from Greylock Partners. Cleo is offered through employers, and provides parents with access to experts in areas like birth preparation and sleep. The app is designed to ease parents' transition back to work, and reduce attrition at…

Why liberal arts and the humanities are as important as engineering

GUEST: Earlier in my academic career, I used to advise students to focus on science and engineering, believing these subjects were a prerequisite for success in business. I had largely agreed with Bill Gates’s assertions that America needed to spend its limited education budgets on these disciplines…
Show more
Report incorrect company information