The business communications app Slack has surely been a media darling over the past 12 months.

Itís got a great founding story and its CEO Stewart Butterfield is not afraid of making controversial comments.

But when it was given a $1.1 billion valuation last October, just 8 months after launching for the general public, there were some question marks surrounding its real value.

Itís probably still too early to gauge its true worth. But its latest numbers, released on Thursday in time for its first year anniversary, tell a story of growth never seen before.

Hereís the takeaway:

Itís making real money: Slack says itís now adding $1 million in annual recurring revenue (ARR) every 11 days, on top of the $12 million in ARR itís built up over the last year. ARR is the total revenue that is expected to repeat for the next 12 months, or as Zuora CEO Tien Tzuo puts it, ďthe gift that keeps giving.Ē Slack also says it has over 135,000 paid accounts now ó all without any meaningful sales and marketing campaigns. Unprecedented user growth: Last February, Slack had about 15,000 daily users when its investor Marc Andreessen tweeted a graph that showed its hockey stick growth. Now, Slack claims to have over 500,000 daily active users, adding tens of thousands of new users each week. Thatís over 33X growth in just 12 months. Itís part of everyday work: Slack users are actively using it for about 2 hours and 15 minutes and are connected to it for over 9 hours each weekday. Theyíre collectively sending 300 million messages every month, which amounted to 1.7 billion messages in the first year. There are currently over 60,000 teams actively using Slack, it says. Itís global: We don't have the exact break down, but Slack's reach is truly global. The top 10 cities for Slack are San Francisco, New York, Tokyo, London, Los Angeles, Toronto, Paris, Chicago, Seoul and Taipei. Thatís 8 different countries across 3 continents. Top 5 countries are the US, the UK, Canada, Japan, and Germany. Users love its compatibility: One of Slackís biggest strengths is its simple integration with 3rd party apps. Slack says it saw over 800,000 individual integrations with other apps like Google Drive, Twitter, GitHub, and Dropbox. More than 3 million messages were sent through these integrations each day, it says.

Here's a graph that shows its crazy growth:

And an infographic:

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