A case interview is a job interview where you solve a business problem out loud with the interviewer: you clarify the goal, structure the problem, ask for and read data, do quick math and recommend what to do. McKinsey, BCG, Bain and Deloitte all use it for consulting roles, and all four say on their own pages that they judge how you reason more than whether you reach one right answer. To practice those skills aloud, Soreno, an AI voice interview practice app for consulting, investment banking and other finance candidates, runs consulting case interviews with an interviewer who pushes back and scored feedback with a next-step plan.
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McKinsey calls it the problem-solving interview, which it says is sometimes referred to as a case interview: a typical client scenario that shows how you approach complex problems. BCG calls it a case study or problem-solving interview, Bain a structured conversation about a real business problem. You get a short prompt, then data when you ask for it, and the interviewer listens to how you reason more than to the final number.
You lead
After your structure, you choose which branch to explore, ask for the data you need and decide when to move on. The interviewer answers and nudges.
They lead
The interviewer asks a set of questions in turn, such as your structure, a chart to read and a calculation. Answer each one fully and sum it up before the next.
Case interview questionsEstimate
How big is a market, or how many of something are sold. It comes alone or inside a bigger case. State the approach, then the numbers, then check the result makes sense.
Market sizing, step by stepOn screen
Solved alone before the live rounds, such as McKinsey's Solve game, BCG's online case (often called Casey) and Bain's digital assessment for some applicants.
How BCG's online case worksOn paper
A pack of slides or data to read alone for a set time, then a recommendation you present and defend. Ask your recruiter which format to expect.
Beyond consulting
Capital One runs case interviews for analyst roles, and product teams use product cases. Same skills, different problems.
Capital One case interview1. Clarify
Say the question back in one sentence and ask two or three questions about the objective and the business. Bain's first tip is to clarify the objective.
2. Structure
Take a moment, then lay out the three or four things you would need to know. McKinsey asks for tailored answers rather than standard frameworks.
How to build an issue tree3. Analysis
Ask for the numbers your structure needs, read charts and tables, and say what each one means for the question, not only what it shows.
4. Math
Say the approach before the numbers, then check the answer is sensible. BCG expects quick calculations and warns against rushing.
Free case math drills5. Recommend
Give the answer, two or three reasons with numbers, the main risk and the next steps, in under a minute. Deloitte's own five steps end the same way: your recommendation, then next steps and the expected impact.
Our suggestion for laying out one sheet of paper. McKinsey allows only pen and paper in its interviews, so practice on paper too.
Top
The client, the question and the goal in a line or two, with every number the interviewer gives. Read it back before you start.
Left
Two to four branches, drawn large enough that you can turn the page and walk the interviewer through it.
Right
Each number with its unit and where it came from, and the math lined up step by step so the interviewer can follow and check it.
Bottom
One line after each finding saying what it tells you. By the end, those lines are your recommendation.
How to make a structure MECEThe case is rarely the whole interview. Each firm pairs it with questions about you.
McKinsey
For most client-facing roles McKinsey runs PEIs as well as problem-solving interviews. It suggests two examples for each of its four areas: Connection, Drive, Leadership and Growth.
McKinsey PEI questionsBCG
BCG's global process lists a skills interview on your experience and motivation, then a case interview and a team interview for client-facing roles.
BCG case interview guideBain
Bain gives every candidate for a role the same questions, and in every role it looks for people who can explain why they want to join Bain in particular.
Consulting behavioral questionsUse these as checklists, then build the structure for the client in front of you.
Profitability
The most common case type. Split profit into price, volume and costs, and find the change before you suggest a fix.
Profitability framework, workedMarket entry
Size the market, check competitors and the client's edge, choose the way in and end with a clear yes or no.
Market entry framework, workedMarket sizing
State the unit, write the formula, round as you go and check the answer another way.
10 market sizing questions, workedStructure
Branches that don't overlap and together cover the question. That is what interviewers mean by MECE.
MECE, with examplesOpening
Break the client's question into three or four parts, then each part into what you would check.
How to build an issue treePractice
Reading frameworks is not practice. Run a whole case with someone who pushes back.
Case interview practice with an AI interviewerA regional bakery chain's profit fell from $10 million to $8 million in a year. The CEO wants to know why, and what to do.
1. Clarify
"So we want to find why profit fell 20% and how to win it back. Has anything changed, such as new stores, products or prices?" The interviewer says it is the same 50 stores and the same menu.
2. Structure
"Profit is revenue minus costs, so first I'll find which one moved. Revenue is customers times spend per visit. Costs are ingredients, labor and rent."
3. Analysis
The interviewer shows revenue up from $100 million to $104 million and costs up from $90 million to $96 million, with labor and rent flat. "Revenue grew 4%, so this is a cost problem, and all $6 million of the rise is ingredients."
4. Math
"Ingredients rose 17%, from 36% of revenue to about 40%. To earn $2 million more on $104 million of sales, prices would need to rise about 2%, if customers buy the same amount."
5. Recommend
"Profit fell because ingredient costs rose $6 million while sales grew only 4%. I'd raise prices about 2% on the items with the highest ingredient cost and renegotiate flour and butter contracts. The risk is customers buying less, so I'd test the new prices in a few stores first."
From McKinsey, BCG, BCG's interview process, Bain, Bain's interviewing page and Deloitte's case tips.
The firms describe the same few things. Reasoning matters more than reaching one right number.
McKinsey asks you to listen carefully and give a tailored answer rather than a standard framework.
BCG lists showing your thinking and communicating clearly, and warns against staying silent.
Bain's tips start with clarifying the objective. BCG asks you to clarify assumptions and ask thoughtful questions.
BCG expects quick calculations and warns against rushing or overcomplicating the answer.
Deloitte's five steps end with your recommendation, then the next steps and the results you expect. Deloitte says the goal is to convey your logic and thought process clearly.
From McKinsey, BCG, Bain and Deloitte's case interview tips.
About an hour a day. Short drills you can do alone, then full cases with a partner or an AI interviewer.
Week 1
Read two firm sample cases end to end, such as McKinsey's Beautify and Bain's Coffee Shop Co. Learn the common case types and do ten minutes of case math by hand every day.
Free case math drillsMcKinsey: pen and paper onlyBain: calculator rulesConsulting case examples
Week 2
Two case openings a day: read the prompt, take a minute, then say your structure aloud in under two minutes. Compare it with the strong opening on the question page.
Week 3
Three or four full cases with a partner or an AI interviewer who asks follow-ups. After each one, write down the single thing to fix next time.
Week 4
The case types that come up most, each with a note on what a strong opening does. More cases with example answers are on our case interview questions page.
Revenue or costs, and which moved.
A regional grocery chain's profits are down 20% in two years. Why?
Split profit into revenue and costs, then ask which moved before guessing why. Practice it, see a model answer
An airline carries more passengers but makes less money. What is going on?
Volume is up, so look at price per seat and cost per seat, and ask for the numbers to compare. Practice it, see a model answer
A software company grows 40% a year and still loses money. What would you do?
Separate the cost of growth from the cost of running the business, then look at what a customer is worth. Practice it, see a model answer
One of three divisions is losing money. Fix it, sell it or close it?
Set out what each option is worth, including costs the division shares with the rest of the company. Practice it, see a model answer
Is the market worth it, and can the client win there?
A European e-bike maker wants to enter the US. Should it?
Market size and growth, competitors, the client's edge, and the way in, ending in a clear yes or no. Practice it, see a model answer
A US coffee chain is considering India. How would you approach it?
Show you know the customer is different, then test whether the economics of one store work. Practice it, see a model answer
A gym chain wants to double revenue in five years. How?
Break the goal into more members, more per member and more locations, and size each lever. Practice it, see a model answer
A streaming service's churn has doubled in a year. How do you find out why?
Ask who is leaving and when, then test price, content and competition against that. Practice it, see a model answer
Brainstorm ways a movie theater chain could grow revenue.
Group the ideas before you list them, so the answer reads as a structure, not a pile. Practice it, see a model answer
Value to the customer, cost, and what competitors charge.
How should a software company price a new add-on?
Start from the value to the customer, then check it against cost and competing products. Practice it, see a model answer
The main competitor just cut prices by 20%. How should the client respond?
Find out why they cut and who switches before recommending a match, a hold or a new offer. Practice it, see a model answer
Should an airline raise its checked-bag fee?
Weigh the extra fee revenue against the passengers and bags it would lose. Practice it, see a model answer
What it is worth, what it costs, and what could go wrong.
A PE firm is considering buying a chain of dental clinics. Should it?
Market, the business itself, the price and the exit, with the biggest risk named. Practice it, see a model answer
Two regional airlines want to merge. How big are the savings?
List the synergies by type, size the largest ones and say what could stop them. Practice it, see a model answer
Should a manufacturer build a second factory?
Demand it would serve, cost and payback, and the cheaper ways to get the same capacity. Practice it, see a model answer
Find where the process breaks.
A hospital's emergency room waits have doubled. How would you approach it?
Follow a patient through the stages and find the one where time has grown. Practice it, see a model answer
A city wants to halve traffic deaths in ten years. Where do you start?
Who dies, where and how, then the measures that address the largest groups first. Practice it, see a model answer
State the approach, then the numbers.
How many cups a day does a new coffee shop need to sell to break even?
Fixed costs over the margin per cup, with each assumption said out loud. Practice it, see a model answer
Estimate the US market for electric scooters.
Pick top-down or bottom-up and say why, then sanity-check the result. Practice it, see a model answer
The CEO walks in. What is your recommendation?
The answer first, two or three reasons with numbers, the risks and the next steps. Practice it, see a model answer
Bain's first tip is to clarify the objective. A structure built for the wrong question costs you the rest of the case.
McKinsey asks for tailored solutions rather than standard frameworks. Use the usual parts of a case as a checklist, then build the structure from this client's question.
Staying silent and rushing are both on BCG's don't list, and Bain asks you to share your reasoning and calculations as you go.
McKinsey's integrity rules allow only pen and paper for notes and calculations. Bain allows a calculator in its online assessment, never in the interviews.
A result with no decision leaves the work half done. Deloitte's steps finish with a recommendation, the next steps and the impact you expect.
From each firm's own careers pages, read on October 23, 2026. None publishes a scoring rubric or how many cases to practice.
McKinseyCalls it the problem-solving interview: a typical client scenario to see how you approach complex problems. It recommends its five sample cases, each three or four questions with suggested answers, and says there is not one logical solution, so listen carefully and tailor your answer rather than use a standard framework.
BCGA realistic business challenge worked step by step: structure your approach, ask questions, analyze data, do quick calculations and find what matters most. It looks for clear communication, logic, business intuition and creativity, and says there isn't always a single right answer.
BainA structured conversation about a real business problem. Bain says it wants to see how you think and structure problems, with no single right answer. Its tips start with clarifying the objective, structuring your thinking, thinking aloud, and listening and adapting to the interviewer. Its sample cases are Coffee Shop Co. and FashionCo.
DeloitteUnderstand the issue, identify the underlying assumptions, summarize the issues and findings, state your recommendations, then outline next steps and expected results. Deloitte US says the goal is to convey your logic and thought process clearly, and points entry-level consulting candidates to its Case Prep Tool.
Good prep gives you three things: real cases, someone who pushes back, and honest feedback on what you said. Five kinds of help can give you those. Choose by how many weeks you have, what you can spend and whether you have a partner. Most candidates combine free cases with one or two ways to get feedback.
The firms' own sample cases, such as McKinsey's five and Bain's Coffee Shop Co. and FashionCo., plus casebooks that business school consulting clubs publish with cases and model answers.
Classmates, a consulting club or other candidates take turns giving each other cases, one as candidate and one as interviewer.
A former consultant or interviewer runs full cases with you one to one and tells you what to change, often including your fit stories.
Video lessons or a program that teaches the case types, a way to structure them, case math and worked examples, sometimes with a question bank.
An AI interviewer gives you a case out loud, asks follow-ups, shows data and then scores what you said. You can practice at any hour, as often as you like.
For example, Soreno (that's us) runs full cases in your browser: an AI interviewer that asks follow-ups, shows charts, checks your math and scores the session. Start your free week. Try a free sample case
Costs are in general terms because they change.
Soreno's AI interviewer runs a whole case with you: it asks follow-ups, shows charts, checks your math and scores the session. Start your free week.
A job interview where you solve a business problem out loud with the interviewer: clarify the goal, structure the problem, ask for and read data, do quick math and recommend what to do. McKinsey, BCG, Bain and Deloitte use it for consulting roles, and some banks and tech companies use it too.
Clarify the goal, structure the problem, analyze the data, do the math and recommend. Deloitte publishes its own five: understand the issue, identify the underlying assumptions, summarize the issues and findings, state your recommendations, then outline next steps and expected results.
Mostly. BCG calls it a case study or problem-solving interview, and McKinsey calls it the problem-solving interview. Outside consulting, a case study interview can also mean a take-home exercise you present later.
McKinsey, Bain and BCG's global case page don't publish a length, so ask your recruiter. Some BCG offices publish their own, listed in our BCG guide.
No firm says. Four weeks of about an hour a day is enough for the plan above. If you have less time, keep the daily math and spoken openings and do fewer full cases.
Firms don't publish a number, and the count matters less than what you fix after each case. Go on until your openings are clear on the first try and your math holds up under questions.
No. McKinsey asks for tailored solutions rather than standard frameworks. Learn the usual parts of a case, then build a structure for the problem in front of you.
Profitability (profits are down, why), market entry, pricing, deals and operations, plus market sizing estimates inside most cases. Our case interview questions page lists them by type with short answers.
Partly. Math, market sizing and spoken openings work alone. Full cases need someone to push back, a partner or an AI interviewer.
Not at McKinsey. Its integrity page says you use only pen and paper for notes and calculations, with no calculator, generative AI, apps or prepared notes. Bain allows a calculator in its digital assessment only, not in the interviews. Practice case math by hand.
Yes. McKinsey lists practicing interview questions and asking AI to explain frameworks as encouraged, and generating answers during a real interview as not allowed.
The prompt and the goal at the top, your structure on the left, data and math on the right, and one line after each finding saying what it means. Write numbers with their units so the math is easy to check.
Say what you're stuck on, go back to your structure and pick the next branch, or ask for the data that would settle it. A short pause is fine. Thinking out loud lets the interviewer see where you are and help you.
A behavioral interview asks about things you have done. A case asks you to solve a business problem live. Consulting firms use both: McKinsey pairs problem-solving interviews with personal experience interviews, and BCG lists a skills interview on your experience before the case.
