How would you estimate the number of Slack users?

To estimate the number of Slack users, I would first clarify the scope: are we considering global users or a specific region like the US? I'd also confirm whether to include both individual and enterprise accounts.

Assuming a global estimate, I'd start with the total number of internet users worldwide. Then, I'd segment this by the percentage of businesses and organizations that are likely to use a communication platform like Slack. I would also consider the adoption rate of such tools in different industries and company sizes.

Alternatively, for a US-specific estimate, I'd begin with the US population, segmenting by age and employment status to identify the working population. From there, I'd estimate the percentage of these individuals who are employed in roles or companies that would utilize Slack, factoring in market penetration and competition from similar tools.