Slack announced today that it has over 1.1 million active users per day, which is significantly up from 500,000 daily users in February. In addition, Slack now has 300,000 paying customers, also up from 135,000 four months ago, and seeing annual recurring revenues of $25 million.
Finally, there are 100 integrations available to Slack users — such as Giphy, Mail Chimp, Crashlytics, and Zendesk — and 900,000 installs.
Slack launched last year by Stewart Butterfield, the Canadian entrepreneur who previously founded Flickr, which was later sold to Yahoo in 2005 for a reported $35 million. Slack was built by Tiny Speck, a Vancouver-based computer game startup founded in 2009. Most of the leadership at Tiny Speck came from Ludicorp, the company that built Flickr.
It's no surprise that Slack has grown the way it has, we use it heavily here at Data McFly, and are even setting it up as a support system shortly for users to chat with each other.