In the wake of news that Microsoft Teams now has over 20 million active daily users, Slack says it has greater engagement.

“As we’ve said before, you can’t transform a workplace if people aren’t actually using your product,” a Slack spokesperson told me. “Slack continues to see unmatched engagement on our platform with 5+ billion weekly actions, including 1+ billion mobile actions. Among our paid customers, users spend more than 9 hours per workday connected to our service, including spending about 90 minutes per workday actively using Slack.”

These numbers need to be understood in context. According to Slack, Microsoft’s numbers—20 million active daily users, 27 million voice or video meetings in the last month, and 220 million open, edit, or download actions on files stored in Teams in the last month—can be used against it: They equate to just over 1 monthly voice/video call and approximately 11 monthly file actions per daily active user.

Put more simply, Slack is claiming that its user base is far more engaged with its service than are Teams users with Microsoft’s.

“Engagement is what makes Slack work,” Slack VP Brian Elliott noted back in October. “You can’t transform a workplace if people aren’t actually using the product. And we love the people building apps and integrations on the Slack platform, because they help drive that engagement. Our developer community has scaled with us to create a thriving ecosystem that feeds this engagement.”

Tagged with Microsoft Teams, Slack