McKinsey Case Interview

The McKinsey case interview is different than the case interview you will receive at BCG, Bain, or another top consulting firm. This means that you must prepare strategically. While best practices are consistent across different case styles, at some point, simply preparing for general case interviews will not put you in the best position to ace your McKinsey case interview.

Table of Contents:

1. The McKinsey Case Interview Overview
2. Bain vs McKinsey and BCG vs McKinsey
3. McKinsey Case Interview Questions
4. McKinsey Case Interview Tips
5. McKinsey Case Interview Prep
6. The McKinsey PEI
7. McKinsey Case Interview Examples

The McKinsey Case Interview Overview

The biggest differentiator of the McKinsey case is that it is interviewer-led rather than interviewee-led. This means that after each piece of the case, the interviewer will tell you what to look at next (instead of you having to decide what to ask for and analyze next).

Even though you may not use your structure to solve the case (as would be necessary with the BCG or Bain interviewee-led case), it’s very important to McKinsey that you build a robust one nonetheless. That’s why, as you prepare, it’s still important to work through interviewee-led cases so you practice being hypothesis-driven throughout the case conversation. This core skill is critical to succeeding in the McKinsey interviewer-led case.

McKinsey’s expectations – and your interview experience – will vary based on whether you are applying for a generalist role or a more specialized position. For a generalist position, expect to see a variety of business problems across functions and industries. When preparing, practice building creative frameworks and ensuring your mental math is on point.

Preparing for your Interview

When preparing for an interview for a specialist role, cases will most likely be related to your industry or functional area (no surprise there). On one hand, this makes it a little easier to prepare because you have an idea of the types of cases you’ll see. On the other hand, the bar to pass is a bit higher. You must demonstrate subject matter expertise (including increased business acumen in your industry and/or function as well as an understanding of industry space, players, and terminology).

Each McKinsey interview isn’t just a case – there are behavioral questions included as well for the first half of the interview (the infamous Personal Experience Interview = PEI). Success isn’t predicated just on your problem-solving ability, but on your leadership, communication skills, and general likability. In final rounds, 50% of your score is driven by the behavioral/PEI component of the interview. Don’t neglect preparing for this!

There are hurdles to clear before you even get to the case interview, including the McKinsey Digital Assessment. These online tests are timed and can include problem solving questions, case simulations, analytical math questions, and strategic games. In some ways, the experience mirrors taking the GMAT.

In the rest of this article, we’ll cover every pressing topic on your mind: McKinsey case interview questions, McKinsey case interview examples, McKinsey case interview tips, the McKinsey PEI, and more.

Let’s look at McKinsey case interviews through the lens of comparing them to the interviews at BCG and Bain.

Bain vs McKinsey and BCG vs McKinsey

Let’s start with the similarities – the top consulting firms look for the same skills: quantitative analysis, problem solving, business acumen, leadership, and communication. Additionally, each will run you through a multi-round process consisting of both case and fit interviews, and each may make you take various digital assessments.

Now for the differences. Scoring for the McKinsey case interview differs from the other top firms. McKinsey scores you on each piece of the case, while Bain and BCG give you a more aggregated score at the end. This means that it’s easier to end strong for Bain and BCG and leave a good lasting impression, while at McKinsey, the interviewer is evaluating each component of your case. This means you must “pass” each question to succeed.

A big difference: McKinsey has a separate Personal Experience Interview (PEI) that is the most intense “fit” interview you’ll see at any consulting firm. Furthermore, McKinsey applies a PEI lens to its case interviews in a way that differentiates it from Bain and BCG. In other words, there is a more robust personality check and behavioral component to McKinsey case interviews.

McKinsey interviewers will control the pace of the interview much more than interviewers at Bain and BCG. At McKinsey, the interviewer will be the one keeping the interview on track (which shouldn’t come as a surprise given it’s the McKinsey “interviewer-led” case). They won’t hesitate to interrupt if you are taking too much time answering a question.

While McKinsey interviewers are not trying to misguide you, they will poke holes in your logic and challenge the quality of your answers. Because McKinsey is so competitive, the interviewers push candidates to find the best of the best. As you begin your preparation process, follow along with multiple McKinsey case interview examples to get a sense for what the back-and-forth interaction is like.

McKinsey Case Interview Questions

There are multiple pieces to a McKinsey case, and multiple types of “mini-cases” that you may see in the McKinsey process. We call these case interview “question types”. Every McKinsey case includes 3-5 different question types and each question is scored independently. They include:

• Framework
• Market sizing
• Brainteasers
• Information gathering
• Math
• Chart insights
• Qualitative questions
• Final recommendation

Framework

Your framework is the foundation of the McKinsey case. It’s the problem-solving approach you will build in response to the business question you’re given. A good way to think about frameworks – if you were the Engagement Manager of a consulting team of 4-5 Business Analysts and Associates, which workstreams would you assign across your team to arrive at a solution to the problem? And what would the key questions be to answer in each of those workstreams?

There are two main ways you can build your framework:

1. 1. Issue trees
   2. Bucket approach

If you stay as mutually exclusive and collectively exhaustive (MECE) as possible, we don’t really care which approach you take, although we do recommend the bucket approach (and these are arguably utilized more often by candidates in the McKinsey interview process).

See an example below from our Case Interview Frameworks: Ultimate Guide

The Pricing Framework

Another common case study interview framework revolves around pricing strategy. Generally, prices greatly impact volume and ultimately profits, so this case study objective comes up quite frequently.

Pricing products and services is a great challenge for companies because prices greatly influence customer decisions. Consulting companies with rich histories and long track records are able to utilize their work with similar previous clients to provide the guidance needed to get the most out of their pricing strategies.

Potential Pricing Framework Categories and Questions:

Product Information

• • • • What is the new product and how is it different from what is currently on the market?
      • How innovative is this product compared to others that exist in the market?
      • Is the product patented or have any rights that can protect it from being copied?
      • Are there similar products in the market that can act as substitutes?
      • Can the product be bundled with any existing products?
      • Will the product cannibalize any of the client’s current products?
      • What were the R&D costs required to create this product?
      • How big is the market for this product?

Competitive Analysis

• • • • How much are competitors charging for similar products?
      • How are competitors thinking about their pricing strategies?
      • Understand- How much does it cost for competitors to create similar products?
      • Are there any substitutions to our client’s product?

Pricing Strategy

• • • • Does cost-based pricing or price-based costing make more sense?
      • What is our breakeven point?
      • How much does it cost to create and deliver the product?
      • Has there been any research completed to see how much customers are willing to pay for the product or similar ones?
      • Do customers need to be educated about the product?
      • What are the potential costs with bringing this product to market?
      • How much will be spent on marketing?

We’ve outlined more common frameworks here. They are a good place to start, but the eventual goal is for you to build your own frameworks inside of the McKinsey interview. One way you can build your own frameworks is to “blend” categories from the different core frameworks to build your own. You must customize your questions within your chosen framework to the exact business case prompt that you’ve been given. This means utilizing case-specific, client-specific, and industry-specific language throughout the presentation of your case structure.

You’ll also need to include insight comments as you talk through the presentation of your structure. Think: Why is this information important? What will I do with this information? What are some examples of this data? These additional insights show off your business acumen and add greatly to drive customization and specificity in your case structure.

Market Sizing / “Guesstimation”

Market Sizing questions are common inside of McKinsey cases – you’ll rarely see this as a standalone case, but many longer cases will include a market sizing question as one component. Here’s an example: Let’s say your client is a jewelry retailer seeking to determine whether it should enter the Danish market. One part of the case may ask you to size the market for diamond rings in Denmark. The goal here is not to be 100% accurate; instead, McKinsey interviewers want to see your thought process in action. Here are the 5 steps to size a market (the top-down approach):

1. 1. Start with population/households/businesses (whatever is most relevant)
   2. Segment again by age/gender/location/frequency of use, etc.
   3. Assume the percentage of the group who own the product or use the service
   4. Segment these “users” by age/gender/location/frequency of use, etc.
   5. Assume a replacement rate
   6. Assume an average weighted price
   7. Calculate the market size in terms of revenue per year

Brain Teasers

You’re most likely to see brain teaser questions in a screening round. One notorious example of this type of question: “How many golf balls fit into a Boeing 747?” Don’t fret! Think outside the box, devise an approach that passes the sanity test, and walk the interviewer through your approach. If you get a question like this, you’re not expected to get an exact right answer. You’re expected to break this (perhaps crazy!) question down into logical bite-sized pieces and then walk through them in a rational order, much in a similar way as we just walked through the example market sizing steps above.

Information Gathering

Knowing how and where to obtain relevant data is a crucial aspect of the job as a consultant. For instance, you must know how to assess your target customer’s preference for, let’s say, ball caps. Strategies could include doing quantitative or qualitative surveys, accessing market research reports, or leveraging historical purchase data. You will most likely utilize information gathering insights in the way that you customize your case structure towards the beginning of the interview, though you could also be asked a creative question to brainstorm various information gathering approaches that are relevant at this point of the case discussion.

Math

You will be asked to perform math calculations during your interview. Our #1 tip? Work efficiently, out loud. Talk through the steps you want to take before you do any calculations. Then talk through the calculations as you do them in your head and write each interim answer down on your paper as you go. Keep math mechanics off your paper and instead perform calculations mentally. Finally, make sure your process is structured. Here’s a look at our recommended approach for math:

• • Recap: Synthesize key aspects to the question and align on all key data shared verbally.
  • Structure: Lay out the math steps you’re going to do before doing any calcs.
  • Calculations: Perform math out loud while engaging directly with the interviewer, keeping track of your answers on your paper.
  • Insights: Layer on additional commentary after you answer each section of the question. Think: What is the impact of this analysis on the client or the case objective? Try to pull together all the information you’ve learned in the case to bring this analysis into context.

Following this approach will give your interviewer insight into your problem-solving approach and thought process (just as important as giving them the correct numerical answer). It will also ensure you end with a business insight, which is the whole point of doing the math to begin with!

And, when you make a mistake (it happens to many), you should be able to easily backtrack through your process to find the error while remaining centered and confident to the interviewer.

Keep in mind – McKinsey is less amenable to letting you round your numbers vs. either BCG or Bain. So, make sure you’re up to speed on your mental math!

Chart Insights

Analyzing data to extract business insights is a routine part of a consultant’s job. Thus, interpreting charts is essential to the McKinsey case interview – you’ll be asked to interpret data in most McKinsey case interview examples. Push yourself to get to 3 levels of insights for each chart you come across:

• • Level 1: What the data is saying
  • Level 2: What it means for the client or case objective
  • Level 3: What information you’d want to gather next based on this data

Qualitative Questions

Business intuition is essential to the case interview performance that McKinsey demands. Throughout the case interview, you’ll be asked to brainstorm ideas in response to qualitative prompts. Even when answering these questions, structure is key – for example, if you’re brainstorming potential cost categories, structure them by fixed vs. variable costs.

This is also the part of the interviewer with the infamous McKinsey “what else?” questions. When brainstorming, your interviewer wants you to come up with as many ideas as possible while maintaining a structure to your delivery. And when you’re done brainstorming and try to move the conversation forward, your interviewer is very likely to ask, “What else?” to make you brainstorm some more. Your goal in that moment is to stay calm and centered and talk it through until you can come up with at least one more idea, even better if you can generate a whole new category of ideas. Your interviewer can ask you “what else?” two or even three times to see how you will respond!

Final Recommendation

The most important part of the job: making a recommendation for what your client should do! The ideal here is to use an “answer-first” approach – lead with a strong final recommendation, back it up with supporting data from the case, and then end with a clear and structured list of the risks and next steps you see. Try to pull both quantitative and qualitative data that you’ve learned throughout the case discussion into your final recommendation to create a strong and specific evidence base to back up your recommendation.

McKinsey Case Interview Tips

The McKinsey interviewer-led case can seem daunting; here are some McKinsey case interview tips to help you start off on the right foot.

1. Focus on Structure Throughout the Case

Utilizing numbered lists, categorizing your thinking, taking brief pauses between thoughts, and staying direct in your communication are all small tricks to help you increase the clarity of your answers.

2. Don’t be Passive

Even though the McKinsey style case interview is interviewer-led, always tell the interviewer where you want to go next after answering a particular question. It’s important to remain hypothesis-driven, derive the implication of each piece of analysis you’ve just completed, and attempt to drive the conversation forward (even though they will direct the flow of the conversation!).

3. Ask Good Clarifying Questions at the Beginning

In the McKinsey style case interview, the interviewer often has all the data you will need to solve the problem. So, ask questions – but in a hypothesis-driven way, and only those where the answer will help you solve the problem. Questions should attempt to limit scope to make it easier for you to build your framework.

Example: “Based on the industry our client is in, I would assume that they operate direct to consumer and do not have a B2B model. Can you confirm this for me?” You put a stake in the ground first and have limited the scope by confirming your understanding of the business model early in the case.

4. Practice Only Rounding To the 1s Place

McKinsey is less enthused about you rounding during the math than other firms. Make your practice difficult so that if you come across a particularly tough interviewer, you’re prepared.

5. Tie Pieces of the Case Together

Insights build on each other. Don’t solve each part of the case like it’s separate…build upon your framework and earlier insights you’ve arrived at. Take in all new information through the lens of the case objective – it’s all connected. Previous answers and insights can and should be used!

6. Be Comprehensive

Don’t be afraid to add commentary like “another thing to consider is…” to show you’ve thought about the question in multiple ways.

7. Use The Pyramid Principle

Always lead with your takeaway first, then follow that up with the supporting facts and logic that explains how you got there. Never save the punchline for the end.

8. Don’t Pause

It is a major faux pas to take a pause in the math in a McKinsey case – You will be expected to perform math quickly and accurately, always driving to the implication (the “so what”) of the analysis. McKinsey interviewers demand quick thinking in every section of the case, especially math.

9. Be confident and direct with your final recommendation

Follow the final recommendation with clear next steps for how to move forward. Do not leave the case interviewer wondering what your recommendation or answer is.

10. Have thoughtful questions prepared for after the case interview concludes

You are still being assessed as you engage the interviewer via personal, specific, and positive follow-up questions. Though this seems like it’s outside the parameters of the McKinsey case interview, any moment you have with the interviewers is a moment you need to impress.

McKinsey Case Interview Prep

Now that we’ve provided some McKinsey case interview tips for the day-of, let’s discuss how you can prepare for the interview – starting right now.

1. Move to out-loud practice ASAP

The case interview is a verbal test as well as a mental one. The quicker you start simulating interview realities, the quicker you’ll be interview ready. The McKinsey style case interview is a performance; would you ever go on stage without rehearsing?

2. Don’t memorize 20 frameworks – trust your business intuition to build your own

Memorization is not the way to prepare for the McKinsey case interview. Memorization leads to forcing answers that might not quite be relevant to the questions asked.

3. Ensure you can extract 3 levels of insight from every math answer / chart

Success is predicated on the use of analytical skills – show off any relevant conclusions that can be inferred from math equations.

4. Bring structure to everything, including your creativity – qualitative questions aren’t an excuse for you to babble

McKinsey consultants structure their approach to every problem!

5. Build your math muscle

McKinsey case interview questions require quick math. Be prepared.

6. Get expert feedback

Work with our McKinsey coaches to ensure you’re ready.

7. Have fun!

An important reminder: interviewers are on your side! In addition, if you don’t enjoy solving simulated business problems, you won’t enjoy life on the job!

Don’t Ignore the McKinsey PEI (Personal Experience Interview)

Although preparing for the behavioral section of the interview doesn’t seem as pressing as the case interview, it is also a make-or-break for candidates. The McKinsey PEI questions you deeply on a single experience from your experience, asking 15-20+ follow-up questions on that same experience. What do the questions focus on? Your personal impact, problem-solving skills, entrepreneurial drive, inclusive leadership, and ability to drive courageous change.

You should come up with 3-5 stories in each of these four categories that you could go deep into. Think: identifying all the stakeholders in those stories, remembering specific conversations, emotions, and potentially even role-playing events of the past with your interviewer. Once you’ve identified these stories, work with a McKinsey coach to refine them and practice the delivery.

Despite the depth of the PEI, you should still answer each individual question within the PEI with a story. Below is a pathway to crafting relevant stories so you can nail the McKinsey PEI. Your stories should be crisp, clear, and concise.

• Provide Context: Set the scene with relevant details about what the problem entailed and why it mattered to your organization/client.
• Identify the Solution: What evidence led you to your solution? Focus on what you did specifically instead of bringing everything back to the team you were on.
• End with Takeaways: What did you do well? What did you learn? What would you have done differently? How did the organization benefit from your actions? Use metrics when possible.

McKinsey Case Interview Examples

Here are some different McKinsey case interview examples straight from the McKinsey website.

In addition, here are McKinsey-specific case walkthroughs our team at Management Consulted has put together.

• Mergers and Acquisitions Case Walkthrough: McKinsey Style- Restaurant Acquisition
• McKinsey Case Interview Example – November 2021
• McKinsey Case Interview Example – December 2021
• McKinsey Case Interview Example – Solved by Consulting Candidate
• McKinsey Case Walkthrough – June 2021
• McKinsey Case Interview Walkthrough

Conclusion

Preparing the right way for the McKinsey style case interview (and McKinsey case interview questions) will give you the best shot at securing an offer at The Firm. Now that you’ve read our guide, it’s time to start practicing! Join our Black Belt program to work with an expert McKinsey coach on one-to-one prep.

 

Additional Reading:

• What Is It Like To Work At McKinsey?
• McKinsey PEI: Personal Experience Interview
• McKinsey Careers
• Case Interview: Complete Prep Guide