Beautify
- Sector
- Retail
- Questions
- 4
- Tests
- Structure, a customer brainstorm, payback math and a chart
Should a global beauty products company train its in-store beauty consultants to reach customers through virtual channels? Walked through above.
McKinsey case interview examples, and how to prepare
McKinsey calls its case interview the problem-solving interview: a typical client scenario you work through in conversation with your interviewer alongside the Personal Experience Interview. McKinsey publishes five official sample cases that each run through three or four numbered questions in sequence. There is no single right framework, and candidates use only pen and paper with no calculator or AI tools.
Updated · Published
- Interviews
- Case + PEI
- For most client‑facing roles
- Official cases
- Five
- Three or four questions each
- Calculator
- Not allowed
- Pen and paper only
- Style
- Interviewer-led
- As candidates describe it
A McKinsey-style case, worked question by question
McKinsey's sample cases give you the client's goal and situation, then numbered questions, each of a different kind. Below is one in that shape, Hartwell Pharmacies, invented for this page, with a strong answer to each question. Cover the answers and try each question out loud first.
Hartwell Pharmacies: walk-in clinics4 questions
Client goal: Hartwell, a chain of 400 drugstores, wants to know whether to open walk-in clinics in its stores. It has run a pilot in 10 stores for a year.
Question 1 · Structure
“What would you look at to decide?”
“I'd look at four things. Demand: how many people would use a clinic in our stores and what they'd pay. The economics of one clinic: setup, running costs and what it brings in, including prescriptions filled in the store. Our ability to run it: staff, licensing and space. And competitors nearby. The economics decide it, so I'd start there.”
Question 2 · Math
“The pilot clinics average 20 patients a day. How fast does one pay back?”
The interviewer adds: $150,000 to set up, $520,000 a year to run, $90 a visit, open 360 days, and half of patients fill a prescription in the store at $15 profit each. “20 × 360 is 7,200 visits, times $90 is $648,000. Less $520,000 that leaves $128,000. Prescriptions add 7,200 × 50% × $15 = $54,000, so $182,000 a year. $150,000 comes back in about 10 months, or 14 without the prescriptions.”
Question 3 · Exhibit
“Here are the pilot stores by location. What do you see?”
The table shows patients a day: urban stores 27, suburban 21, rural 4. “The 20 average hides the answer. Each patient brings $90 plus $7.50 from prescriptions, $97.50, so a clinic covers its $520,000 at about 15 patients a day. Urban and suburban clinics clear that easily. A rural clinic at 4 a day would lose about $380,000 a year.”
Question 4 · Recommend
“The CEO walks in. What do you tell her?”
“Open clinics in the 320 urban and suburban stores, not the 80 rural ones. In the pilot those clinics see 21 to 27 patients a day, well above the break-even of about 15, and pay back in under a year. At pilot rates that is about $95 million a year for $48 million of setup. The risk is that the pilot stores were the best sites, so I'd roll out in waves and watch patients a day.”
McKinsey's Beautify, question by question4 questions
A global prestige cosmetics company asks whether training most of its in-store beauty consultants to sell through virtual channels could be profitable.
1. Structure
What should the company weigh?
A list of factors to consider before moving the consultants to new roles. Group them, say for the people, the customers and the costs, so the list reads as a structure.
How to build an issue tree2. Brainstorm
Think like the customer
You play a loyal in-store shopper and say what would make you switch to a mostly virtual experience. Ideas from the customer's side, grouped, then the one or two that matter most.
3. Math
When does it pay back?
Beautify has €1.3 billion in revenue, expects a 10% incremental revenue lift, invests €150 million upfront (€50M IT, €25M training, €50M remodeling and €25M inventory) with 5% annual IT depreciation, and pays €10 million a year in ongoing costs. McKinsey's hint: calculators are not allowed, so write your math on paper and talk the interviewer through each step.
Free case math drills4. Exhibit
Read the chart, then recommend
An exhibit compares four competitor AI chatbots, Clarice, Lena, Jaki and Lola, across customer metrics. State what the data shows, spot the non-obvious trend across the four bots, and recommend what Beautify should do next.
How to read case interview charts
From McKinsey: Beautify practice case and McKinsey's interviewing page.
What McKinsey looks for in the case
McKinsey does not publish a scoring rubric. Its interviewing page says this much:
A tailored answer
Listen carefully and build a solution for this client, rather than reach for a standard framework.
More than one good answer
McKinsey says there is not one logical solution. Your approach to the problem is what it evaluates.
A conversation
It calls the case a problem-solving conversation, and tells candidates to ask the interviewer to repeat anything unclear.
Practice on its own cases
McKinsey recommends its sample cases to learn the types of questions it asks and how the conversation goes.
McKinsey's five sample cases
Published on McKinsey's interviewing page with the logic, thought process and suggested answers. Each is a short brief and three or four numbered questions. What each tests is in our words.
Diconsa
- Sector
- Social sector
- Questions
- 4
- Tests
- Structure, savings math, a survey chart and a brainstorm
Could the Diconsa store network in Mexico offer basic financial services to the rural poor? The client is the Gates Foundation.
Electro-Light
- Sector
- Beverages
- Questions
- 3
- Tests
- Launch factors, market and consumer data, what a 12.5% share takes
Designing the launch of a flavored, reduced-sugar sports drink for a major beverage company.
National education
- Sector
- Public sector
- Questions
- 3
- Tests
- Diagnosis, a country comparison chart and testing a client's idea
Diagnosing problems in a country's national education system and assessing ways to transform it.
Talbot Trucks
- Sector
- Trucks
- Questions
- 3
- Tests
- What to find out, a cost of ownership comparison and price math
Should a leading European truck manufacturer invest in making and selling electric trucks?
How McKinsey's process runs
For consulting roles, as McKinsey describes it. Your recruiter confirms the details.
Step 1
Application
Depending on the role, McKinsey may ask you to take a test or play a game as part of the application.
Step 2
Solve
A gamified problem-solving assessment for most consulting roles. McKinsey says no preparation is needed, and AI tools and notes are not allowed.
Step 3
Case and PEI interviews
Problem-solving (case) interviews and personal experience interviews for most client-facing roles. Some roles add an expertise interview. Candidates invited to interview get McKinsey's AI Prep Tool for the quantitative part of the case.
From McKinsey's careers pages.
15 McKinsey-style case questions
Candidates describe McKinsey cases as a series of separate questions from the interviewer. By kind, with what a strong answer does.
Structure the problem
Usually the first question. Take a minute, then lay it out.
A regional grocery chain's profits are down 20% in two years. How would you find out why?
Revenue and costs first, each split one level further, then say which part you would look at first and why.
A European e-bike maker wants to enter the US. What would you need to know?
Market, competition, the client's edge and the way in, tied to the decision the client has to make.
A city wants to halve traffic deaths in ten years. How would you approach it?
McKinsey's own cases include public sector work. Start from who is hurt, where and how.
Should a PE firm buy a regional chain of dental clinics?
Market, the business, price and exit, with the one risk that could sink the deal named early.
Do the math
Say the approach, then the numbers, then what they mean.
How many cups a day does a new coffee shop need to sell to break even?
Fixed costs over the margin per cup. Round sensibly and say the answer as a decision, not just a number.
Two regional airlines are merging. How large are the cost savings?
Set out the synergy types, size the two largest, and flag what would delay them.
A packaging maker's cost per unit is up 15% in two years. Where did it go?
Split unit cost into its parts and find which moved, checking volume as well as prices.
Size a market
A clear method beats a precise number.
Estimate the US market for electric scooters.
Pick top-down or bottom-up and say why, then sanity-check the result against something you know.
Estimate the annual US market for dog food.
Dogs, food per dog by size, price per pound. Keep the segments few and the math clean.
Brainstorm
Ideas in groups, so the answer has a structure.
What are the ways a movie theater chain could grow its revenue?
Group ideas into more visits, more spent per visit and new uses of the space before listing them.
A streaming service's churn has doubled. What could explain it?
Causes on the customer side, the product side and the market side, then how you would test each.
A food bank's demand is up 30% and donations are flat. How could it close the gap?
More supply, less waste and better targeting, with the fastest options first.
Recommend
The answer first, then the reasons.
The CEO walks in. What do you recommend?
Your answer in one sentence, two or three reasons with numbers, the main risk and the next step.
One of three divisions is losing money. Fix, sell or close?
Compare the three on value and risk, include shared costs, and pick one.
Should a consumer goods company launch a premium pet food line?
Is the segment big and growing, can the client win in it, and does it pay back. End in yes or no.
Where McKinsey candidates slip
A framework recited from memory
McKinsey asks you to listen carefully and share tailored solutions rather than standard frameworks. Build the structure from this client's question.
Math in silence
Beautify's hint is to talk the interviewer through your steps, because the more you talk, the easier it is for them to help.
Rushing the numbers
The same hint says not to feel rushed into calculating. Take the time to set up the calculation and check the result.
Practicing with a calculator
McKinsey allows only pen and paper for notes and calculations in its interviews, so a calculator habit shows up on the day.
Leaving the PEI for last
The personal experience interviews come in the same rounds. McKinsey suggests two examples for each of its four areas, so start the stories early.
How to prepare for a McKinsey case
McKinsey's own advice first. The last three steps are our suggestions.
McKinsey's advice
Work its five sample cases
McKinsey recommends them to learn the types of questions it asks and how the conversation goes. Answer each question out loud before you reveal McKinsey's answer.
McKinsey's rules
Pen and paper, no AI
Its integrity page rules out calculators, generative AI, apps and prepared notes in any assessment or interview. McKinsey's interviewing page lists practicing interview questions with AI as encouraged.
Our suggestion
Ten minutes of math a day
Percentages, growth and payback by hand, said out loud, until you can do them without losing the thread of the case.
Our suggestion
Full cases, one question at a time
Practice with someone who asks McKinsey-style questions in turn and pushes back, a partner or an AI interviewer. Start with the free sample case, no sign-up needed.
Our suggestion
Your PEI stories
Two stories for each of Connection, Drive, Leadership and Growth, each told with your own role and reasoning in the detail.
Practice the McKinsey way, out loud
Soreno's McKinsey-style interviewer leads you through a case one question at a time, shows exhibits, checks your math and scores the session.
Questions people ask
What is the McKinsey case interview?
McKinsey calls it the problem-solving interview, sometimes referred to as a case interview: it presents a business case based on a typical client scenario to see how you approach complex problems. For most client-facing roles it comes with personal experience interviews.
Where can I find McKinsey case interview examples?
On McKinsey's interviewing page: Beautify, Diconsa, Electro-Light, a national education system and Talbot Trucks, each with suggested answers. This page works one McKinsey-style case question by question, walks through Beautify's questions and adds 15 McKinsey-style questions of our own.
What does a McKinsey case interview example look like?
A short brief with the client's goal and situation, then three or four numbered questions: usually a structure question, some math, a chart or table to read and a recommendation or brainstorm. The Hartwell Pharmacies case above follows that shape.
How long is a McKinsey case interview?
McKinsey does not publish a length or a number of rounds. Your recruiter confirms the interview details in advance.
Is the McKinsey case interview interviewer-led?
McKinsey does not say. Candidates and prep guides describe it as interviewer-led, with the interviewer asking a set of separate questions, and Soreno's McKinsey style runs that way.
How do I prepare for Solve?
McKinsey says no preparation is needed and that Solve is considered together with the rest of your application. AI tools, other apps and pre-prepared notes are not allowed.
Can I use a calculator in a McKinsey case?
Practice without one. McKinsey says that in its assessments and interviews you use only pen and paper, with no calculator, generative AI, apps or notes, unless McKinsey has approved a disability accommodation.
Does McKinsey use AI in its interviews?
It says it is piloting a small number of AI-enabled interview experiences and that candidates are told in advance. Candidates invited to interview also get access to its AI Prep Tool for the case math.
Do I need frameworks for a McKinsey case?
Not memorized ones. McKinsey asks you to listen carefully and give a tailored answer rather than a standard framework.
What else is in a McKinsey interview?
For most client-facing roles, personal experience interviews (PEI) about stories in four areas: Connection, Drive, Leadership and Growth.
What happens if you make an arithmetic slip during a McKinsey case?
McKinsey's Beautify case hints advise candidates not to feel rushed into calculations, to write calculations out on paper since calculators are not allowed, and to talk the interviewer through each step so the interviewer can see an organized approach and help if needed. As practice advice, state your formula in words before computing numbers.
Can a McKinsey interviewer ask to see your scratch paper during a case?
Yes. McKinsey's Assessment Integrity Expectations state that candidates may use only pen and paper for notetaking and calculations, that interviewers may ask to review your notes during the interview to better understand your thought process, and that your camera must be positioned to show your full upper body and hands.
How do you answer the chart and exhibit questions in McKinsey cases?
As practice advice, take a moment to review the exhibit, note what you see, look for trends that are not obvious at first glance, and then tie those trends back to the client's decision.
How should you open the structure question at the start of a McKinsey case?
McKinsey's interviewing page notes that there is not one logical solution and asks candidates to listen carefully and share tailored solutions rather than standard frameworks. As practice advice, name three or four buckets built specifically around the client's business model and give two concrete drivers inside each bucket.
Keep going
- Best case interview prep, compared
- Case interview examples, 7 worked
- McKinsey salary by level
- McKinsey internship
- McKinsey PEI questions
- McKinsey interview questions
- Free McKinsey-style practice case
- What a case interview is and how to prepare
- McKinsey Solve
- McKinsey AI interview
- Consulting resume
- MECE, with examples
- Hypothesis-driven case interview
- Interviewer-led vs candidate-led cases