As the PM for Gmail, what is your storage purchasing plan for the upcoming year?

This question involves estimating a product and assesses your ability to make assumptions, navigate complex calculations, and think critically. The interviewer is not looking for the precise amount of storage that Gmail will require for the upcoming year, but rather wants to observe your logical reasoning, your approach to making assumptions and calculations, and how you express your thought process. Here are some important factors to keep in mind when crafting your response: The estimated total number of Gmail users worldwide. Understanding the average storage usage per Gmail user. Considering the growth rate of Gmail's user base.

A good starting point would be to estimate the total number of Gmail users worldwide. Based on available public data, we can say there are approximately 2 billion Gmail users. If we consider that the average email size is around 75KB and an average user receives about 30 emails daily, this results in roughly 0.00225GB of data per day. Over the course of a year, this would amount to approximately 0.8GB of storage needed per user. Taking into account the anticipated growth of Gmail's user base, let's project a 20% increase in users over the next year, which would raise the total user count to 2.4 billion. By multiplying the number of users by the storage requirement per user, we can estimate that Gmail will require around 1.9 billion GB, or 1.9 Exabytes, of storage for the upcoming year. This calculation illustrates the process of estimating large figures and applying a growth rate to an initial number, while also accounting for individual email storage usage to determine the overall storage needs for all users.

Let's assume that Gmail has approximately 2 billion users globally. If we consider that each user receives an average of 20 emails daily, and each email is about 100KB, this results in a daily storage requirement of 0.002GB per user, which totals around 0.7GB per year for each user. As Gmail's user base is projected to grow steadily, let's factor in a 25% increase for the next year, raising the total user count to 2.5 billion. By multiplying the number of users by the storage requirement per user, we estimate that Gmail will require about 1.75 billion GB, or roughly 1.75 Exabytes, of storage for the coming year. Overall, this analysis not only reflects a solid grasp of product estimation but also highlights the various factors that contribute to Gmail's total storage needs, including user behavior and the expansion of its consumer base.