I worked for Google from 2006 to 2008, and I interviewed hundreds of Google candidates.
What to Expect
There are five components to the Google product manager (PM) interview:
- Product design. Google PMs put users first. PMs are zealous about providing the best user experiences. It starts with customer empathy and always includes a passion for products, down to the smallest details. They can sketch a wireframe to convey an idea to a designer. Sample questions include:
- How would you improve Google Maps?
- How would you reduce Gmail storage size?
- How would you improve restaurant search?
- What’s favorite Google product? What do you like or not like about it?
- If you were to build the next killer feature for Google, what would it be?
- You’re part of the Google Search web spam team. How would you detect duplicate websites?
- Analytical. Google PMs are fluent with numbers. They define the right metrics. They can interpret and make decisions from A/B test results. They don't mind getting their hands dirty. Sometimes they write SQL queries; other times, they run scripts to extract data from logs. They make their point by crisply communicating their analysis. Some examples of analytical questions:
- How many queries per second does Gmail get?
- How many iPhones are sold in the US each year?
- As the PM for Google Glass 'Enterprise Edition' PM, which metrics would you track? How do you know if the product is successful?
- Cultural fit. Google PMs dream of the next moonshot idea. They lead and influence effectively. They have a bias for action and get things done. If Google PMs were working anywhere else, they’d probably be CEOs of their own company. Sample questions to assess cultural fit:
- Why Google?
- Why PM?
- Technical. Google PMs lead product development teams. To lead effectively, PMs must have influence and credibility with engineers. During the final round (aka onsite) interview, a senior member of the engineering team will evaluate your technical competence. Be prepared for whiteboard coding questions at the onsite interview. Example questions include:
- Write an algorithm that detects meeting conflicts.
- Strategy. Google PMs are business leaders. As a result, they must be familiar with business issues. It’s not necessary for PMs to have business experience or formal business training. However, they do expect you to pick up business intuition and judgment quickly. Sample interview questions include:
- If you were Google’s CEO, would you be concerned about Microsoft?
- Should Google offer a StubHub competitor? That is, sell sports, concert, and theater tickets?
Also be prepared for behavioral interview questions such as Tell me a time when you had to influence engineering to build a particular feature. Google PM interviewers are relying more on behavioral interview questions in recent months.
What Not to Expect
Brain teasers, such as logic puzzles, are rarely used in today’s Google PM interviews. Google’s HR department found a low correlation between job performance and a candidate’s ability to solve brain teasers. Examples of brain teasers include
- I roll two dice. What is the probability that the 2nd number is greater than the 1st?
- What’s 27 x 27 without using a calculator or paper?
However, hypothetical questions have not been banned at all. Hypothetical questions are imaginary situations that ARE related to the job. (This is in contrast with brain teasers, which ARE NOT related to the job.) Examples of hypothetical questions include How would you design an algorithm to source data from the USDA and display on Google nutrition?
How to Prepare
Here's what I'd recommend to get ready for the Google PM interview:
- Product design. Practice leading design discussions using a framework. (Need a framework? Try my . Start with possible personas and detail use cases. Prioritize use cases and brainstorm solutions. Many PM candidates (wrongly) suggest solutions that are incremental or derivatives of a competitor’s feature set. The Google interviewers are evaluating your creativity, and they place a big emphasis on big ideas (aka “moonshots”). Inspire them with unique, compelling ideas. Drawing wireframes on a whiteboard will help illustrate your ideas. To practice, download a wireframing tool like Balsamiq. Also study popular web and mobile design patterns for inspiration.
- Technical. Coding questions are unlikely during the phone interviews. But if you are invited to an on-site interview, you must prepare for programming interviews. The technical interviewer does not expect your programming syntax to be perfect, but you should have sufficient mastery of technical concepts so that you can participate in technical discussions and help make technical trade-offs. I would recommend going over computer science fundamentals and practicing a couple coding questions. Also be prepared to describe key technologies including search engines, machine learning, and MapReduce.
- Analytical. Prepare for estimation questions such as How many queries per second does Gmail get? Get well-versed in product launch metrics and A/B testing, including interpretation of results.
- Strategy. Use a framework to structure your strategy discussions. If you’re not familiar with strategy or frameworks, Porter’s Five Forces is a good start.
- Cultural fit. Understand what it means to be Googley by reading In the Plex: How Google Thinks, Works, and Shapes Our Lives. . Review Google’s . Optional readings: and Steven Levy’s 2007 (but still useful) article on the . Another optional, but more in-depth (and recent) perspective, read Steven Levy’s