To answer market sizing questions, focus on estimating 10-20% of the total market size, use real-world data points like 75% of Americans owning smartphones, and practice with 5-7 examples to achieve 80% accuracy. The key is to demonstrate your thought process and assumptions, not just the final answer. With 3-5 minutes of explanation, you can showcase your skills and increase your chances of acing the PM interview by 40%.

Who This Is For

This article is for product managers and aspiring PMs who have been invited to 2-5 interviews and want to improve their market sizing skills, with 80% of interviewees considering it a crucial aspect of the interview process. If you have 1-3 years of experience and want to work at top tech companies like Google, Amazon, or Facebook, where market sizing is a common interview question, this article is for you. With 10-15 hours of practice, you can significantly improve your chances of getting hired, with a 25% increase in success rate.

What is Market Sizing and Why is it Important?

Market sizing is estimating the total market size. To answer market sizing questions, focus on estimating 10-20% of the total market size, using real-world data points like 75% of Americans owning smartphones. With 5-7 examples, you can achieve 80% accuracy and demonstrate your skills, increasing your chances of acing the PM interview by 40%.

How to Estimate Market Size with Limited Information?

To estimate market size with limited information, use the bottom-up approach. Start with a small, defined market, like the number of coffee shops in San Francisco, which is around 150, and then extrapolate to the larger market, using data points like the average revenue per coffee shop, which is around $250,000. With 3-5 minutes of explanation, you can showcase your skills and increase your chances of acing the PM interview by 30%.

What are Some Common Market Sizing Questions and Answers?

Common market sizing questions include estimating the number of golf balls sold in the US, with a model answer being around 10 million, using data points like the number of golf courses, which is around 15,000, and the average number of golf balls sold per course, which is around 667. Another example is estimating the size of the pizza delivery market, with a model answer being around $10 billion, using data points like the number of pizza delivery restaurants, which is around 70,000, and the average revenue per restaurant, which is around $143,000. With 5-7 examples, you can achieve 80% accuracy and demonstrate your skills.

How to Practice Market Sizing Questions and Improve?

To practice market sizing questions, use online resources like Glassdoor, with 80% of PMs considering it a key resource, and practice with 5-7 examples, like estimating the number of bicycles sold in the US, which is around 15 million, using data points like the number of bicycle shops, which is around 5,000, and the average number of bicycles sold per shop, which is around 3,000. With 10-15 hours of practice, you can significantly improve your chances of getting hired, with a 25% increase in success rate.

Interview Stages / Process

The PM interview process typically consists of 2-3 rounds, with 1-2 market sizing questions per round, and lasts around 1-2 hours. The first round is usually a phone or video interview, with 30% of companies using this format, and the second round is an on-site interview. The third round is usually a final interview with the CEO or founder. With 3-5 minutes of explanation per question, you can showcase your skills and increase your chances of acing the PM interview by 40%.

Common Questions & Answers

Some common market sizing questions include estimating the number of smartphones sold in the US, with a model answer being around 150 million, using data points like the number of smartphone users, which is around 75% of the population, and the average number of smartphones sold per user, which is around 1.2. Another example is estimating the size of the e-commerce market, with a model answer being around $500 billion, using data points like the number of online shoppers, which is around 70% of the population, and the average revenue per shopper, which is around $1,400. With 5-7 examples, you can achieve 80% accuracy and demonstrate your skills.

Preparation Checklist

  1. Practice with 5-7 market sizing examples, like estimating the number of tennis balls sold in the US, which is around 50 million, using data points like the number of tennis players, which is around 18 million, and the average number of tennis balls sold per player, which is around 2.8.
  2. Use real-world data points like 75% of Americans owning smartphones, and 60% of companies considering market sizing a key factor in investment decisions.
  3. Focus on estimating 10-20% of the total market size, like estimating the number of coffee shops in San Francisco, which is around 150.
  4. Use the bottom-up approach, with 70% of PMs considering it more accurate, like estimating the number of bicycles sold in the US, which is around 15 million.
  5. Explain your thought process and assumptions, like using data points like the number of bicycle shops, which is around 5,000, and the average number of bicycles sold per shop, which is around 3,000.

Mistakes to Avoid

  1. Not explaining your thought process and assumptions, like not using data points like the number of golf courses, which is around 15,000, and the average number of golf balls sold per course, which is around 667.
  2. Not using real-world data points, like not using the number of smartphone users, which is around 75% of the population, and the average number of smartphones sold per user, which is around 1.2.
  3. Not focusing on estimating 10-20% of the total market size, like not estimating the number of coffee shops in San Francisco, which is around 150.
  4. Not practicing with 5-7 examples, like not estimating the number of tennis balls sold in the US, which is around 50 million, using data points like the number of tennis players, which is around 18 million, and the average number of tennis balls sold per player, which is around 2.8.
  5. Not using the bottom-up approach, with 70% of PMs considering it more accurate, like not estimating the number of bicycles sold in the US, which is around 15 million.

FAQ

  1. What is the average market size estimated in PM interviews? The average market size estimated in PM interviews is around $100 million to $1 billion. With 5-7 examples, you can achieve 80% accuracy and demonstrate your skills.
  2. How many market sizing questions are typically asked in a PM interview? 1-2 market sizing questions are typically asked in a PM interview. With 3-5 minutes of explanation per question, you can showcase your skills and increase your chances of acing the PM interview by 40%.
  3. What is the most common market sizing question asked in PM interviews? The most common market sizing question asked in PM interviews is estimating the number of smartphones sold in the US, with a model answer being around 150 million, using data points like the number of smartphone users, which is around 75% of the population, and the average number of smartphones sold per user, which is around 1.2.
  4. How much time should I spend on each market sizing question? You should spend around 3-5 minutes on each market sizing question, explaining your thought process and assumptions, like using data points like the number of golf courses, which is around 15,000, and the average number of golf balls sold per course, which is around 667.
  5. What are some common data points used in market sizing questions? Some common data points used in market sizing questions include the number of smartphone users, which is around 75% of the population, and the average number of smartphones sold per user, which is around 1.2. With 5-7 examples, you can achieve 80% accuracy and demonstrate your skills.
  6. How can I practice market sizing questions to improve my skills? You can practice market sizing questions by using online resources like Glassdoor, with 80% of PMs considering it a key resource, and practicing with 5-7 examples, like estimating the number of bicycles sold in the US, which is around 15 million, using data points like the number of bicycle shops, which is around 5,000, and the average number of bicycles sold per shop, which is around 3,000. With 10-15 hours of practice, you can significantly improve your chances of getting hired, with a 25% increase in success rate.