Ultimate Guide: Product Estimation Questions
Doing math in an interview? When they ask you the expected impact of a feature, you have to... Here's everything you need to know to rock those dreaded estimation questions.
Product estimation questions are a new breed of question for many PMs.
(Had you even heard of them?)
Well, they’re ubiquitous - and they’re no walk in the park:
How many customer support tickets might we receive if we launch a new feature to our existing user base?
What's the expected increase in user engagement if we implement a personalized recommendation system?
If we introduce a freemium model for our SaaS product, what percentage of free users might convert to paid users in the first six months?
They test your ability to break down complex problems, make reasonable assumptions, and perform quick mental math.
It's the perfect encapsulation of the analytical side of PM - and why this interview type is so popular.
But to succeed in today's tough market requires a blend of tried-and-true strategies plus unconventional insights.
That's what today's piece is for.
(And I’ll share example answers to all 3 of those questions above.)
Tried and Tested Strategies
I've done hundreds of estimation questions in my career - as a candidate and interviewer. So I had a good idea of what to do in this post.
But to really firm up my advice, over the last 12 months, I took on the added challenge of helping folks who were struggling with estimation questions.
It’s been trial and error - but we’ve figured out a taxonomy of Estimation questions and how to address each.
So, today, I'm ready to crack open the advice column for you.
(You’ll notice this one took a bit longer than product sense, execution, technical, and behavioral.)
Today’s Post
Here's the outline for our journey over the next 9,000 words:
Part 1: The Basics
History of Estimation Questions
Common Users of Estimation Questions
What do Estimation Questions Actually Test?
Part 2: The Techniques
Principles + Frameworks
Unconventional Techniques to Stand Out
How to Avoid the Most Common Mistakes Candidates Make
Part 3: Question Response Examples
1 In-Depth Example of Each of the 6 Types of Estimation Questions
Part 4: Presenting Your Estimate and Handling Follow-ups
Presenting Your Estimate
Handling The 5 Follow-Up Types
Post-Script: The Validity of Estimation Questions
It's the value of a $1000 course - as part of one of the 100 articles you receive a year for $150.
Part 1: The Basics
1.1 History of Estimation Questions in Product Management
Estimation questions, perhaps obviously to some, have their roots in management consulting. But over time, they've made their way squarely into the tech industry, particularly for product management (PM) roles.
The shift towards more structured estimation questions for PMs began in the late 1990s and early 2000s, coinciding with the dot-com boom. As tech companies grew rapidly, they needed a way to assess candidates' ability to think analytically about product-related challenges.
Companies like Google and Amazon were the early adopters, adapting estimation techniques to focus on user behavior, market size for new products, and potential impact of product decisions.
These questions were designed to assess not just analytical skills, but also creativity and the ability to work with limited information - qualities essential for product managers in fast-paced tech environments.
By the 2010s, estimation questions had become a staple in PM interviews across various tech companies. Facebook (now Meta), Apple, and countless startups incorporated these questions into their hiring processes for product roles.
The evolution of estimation questions for PMs reflects the changing nature of product management:
Early tech adopters used them to test analytical rigor and market understanding.
As data became more central to product decisions, questions evolved to assess a candidate's ability to work with metrics and make data-driven decisions.
Modern tech companies use them to evaluate a candidate's ability to think about scale, understand user behavior, and estimate the impact of product changes.
Today, estimation questions are a core part of many PM interview processes.
They've evolved from simple market sizing exercises to complex scenarios that might involve user engagement metrics, feature adoption rates, or revenue projections for new products.
As we move into the 2020s, with the rise of AI and big data, estimation questions for PMs are evolving once again.
They're now often used to assess a candidate's ability to think about personalization at scale, understand the implications of machine learning on product metrics, and consider the ethical implications of product decisions.
Understanding this history not only gives you context but also helps you appreciate why these questions are asked and what interviewers are really looking for.
1.2 Most Common Users of Estimation Questions in Tech
The use of estimation questions spans various roles in the tech industry, each adapting the technique to its specific needs.
In product management, companies like Google, Facebook (Meta), Amazon, and Apple use these questions to assess a candidate's ability to think about product metrics, user behavior, and market opportunities.
They're looking for PMs who can make data-driven decisions and estimate the impact of product changes.
Each of the tech giants have their own spin:
Google might ask you to estimate the number of Gmail users who would adopt a new feature.
Meta (Facebook) could ask about the potential engagement increase from a new News Feed algorithm.
Apple could ask about the market size for a new wearable device.
Amazon might want you to estimate the impact on Prime subscriptions if they introduced a new benefit.
They might label them differently, but each is a flavor of Product Estimation question.
Even smaller tech companies and startups use these questions to evaluate a PM's ability to think about growth and scale.
Across the tech industry, certain roles are more likely to face these questions:
Product Managers (obviously)
Growth Managers focusing on user acquisition and retention
Data Scientists working on product analytics
UX Researchers estimating user behavior changes
Marketing Managers, especially in product marketing roles
The key takeaway? If you're aiming for a product-related role in tech, being prepared for estimation questions isn't just helpful - it's essential.
1.3 What do Estimation Questions Actually Test for PMs?
At their heart, estimation questions probe for a set of core competencies crucial in product management roles. There’s 10 competency areas that fall into 3 buckets:
The Core Competencies
Structured Thinking
Interviewers watch how you organize your thoughts about user segments, feature adoption, or market opportunities.
Analytical Prowess
Your ability to work with product metrics, make reasonable assumptions about user behavior, and perform quick calculations is under the microscope.
Product Sense
These questions test your intuition about user needs, product-market fit, and how changes might impact user behavior.
Market Understanding
Your grasp of the tech landscape, user trends, and potential opportunities comes into play.
Growth Mindset
Can you think creatively about user acquisition, engagement, and retention strategies?
Beyond the Numbers
While quantitative skills are important, estimation questions for PMs dig deeper:
Business Acumen
Your understanding of how product decisions tie to business outcomes is crucial.
Comfort with Ambiguity
In product management, you'll rarely have all the data you need. These questions test your ability to make progress with incomplete information.
Communication Skills
Throughout the process, you're demonstrating your ability to articulate product strategies and data insights clearly.
The Hidden Evaluations
Some aspects of these questions are less obvious but equally important for PM roles:
Stakeholder Management
Can you defend your estimates and product decisions convincingly?
Cross-Functional Understanding
Do your estimates and assumptions demonstrate an understanding of different aspects of the business (engineering constraints, marketing channels, etc.)?
It’s not like they are trying to concoct things to weed people out. The idea is to test skills that really matter to PMs.
Part 2: The Techniques
Now that we understand the basics, let's dive into the techniques to excel. This section will cover both tried-and-true strategies and some unconventional approaches to stand out.
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