Market Sizing: Daily Active WhatsApp Conversations Across India

Estimate how many WhatsApp chats take place across India on a typical day. State your assumptions, show the arithmetic, and explain how you would check that the answer is reasonable. ```hint Pin down the unit Decide what counts as one chat before estimating anything, and remember that a single conversation involves at least two users, so per-user figures need care when you add them up. ``` ### Clarifying Questions - Does a "chat" mean a conversation thread that is active that day, or each individual message sent? - Do group chats count, and should a group conversation count once or once per member? - Are business accounts, broadcast messages, voice and video calls, and status updates in scope? - Does "in India" mean users with Indian phone numbers, or only conversations where every participant is in India? ### What a Strong Answer Covers - An explicit definition of a chat and a statement of what is in and out of scope. - A funnel from India's population to daily WhatsApp users, with every ratio stated as an assumption. - Per-user activity segmented by type of user and split between one-to-one and group conversations. - Correct handling of shared conversations so they are not counted once per participant. - A sanity check from an independent angle, and the assumptions that drive most of the uncertainty. ### Follow-up Questions - How would your estimate change on a major festival day such as Diwali? - If the interviewer meant messages rather than conversations, how would you convert your answer? - Which single assumption moves your result the most, and how would you narrow it with public data?