Case interview examples you can actually practice
Most case interview examples online read like textbook summaries. They walk you through a finished answer and leave you thinking, "OK, but how would I get there in a live interview?"
These four cases are different. Each one gives you a scenario, a set of questions the interviewer would ask, and a walkthrough that shows the thinking behind each step. They cover the four types you will see at McKinsey, BCG, Bain, Deloitte, and most other strategy firms.
1. Profitability case: BrightBean Coffee
The prompt
BrightBean Coffee is a specialty coffee chain with 120 locations across the US Midwest. Revenue grew 12% last year, but profit dropped 18%. The CEO wants to know what happened and how to fix it.
How to structure this
This is a classic profitability case. Profit is down while revenue is up, which means costs are the problem. But don't jump straight to "costs went up" — the interviewer wants to see you break it apart.
Start with the profit equation: Profit = Revenue - Costs. Revenue went up, so acknowledge that and move to costs. Then split costs into fixed (rent, salaries, equipment leases) and variable (coffee beans, milk, cups, labor hours).
Walkthrough
Step 1: Confirm the revenue side is healthy
Ask whether the 12% growth came from new stores, higher prices, or more customers per store. If it was all new stores and same-store sales are flat, that tells you something different than organic growth.
Step 2: Break down costs
The data shows BrightBean opened 15 new locations last year. Rent per location stayed the same, but they moved to a premium bean supplier (cost per pound up 30%) and hired barista trainers at each region (new fixed cost).
Step 3: Quantify the impact
The bean cost increase alone accounts for roughly $4.2M in added expense. The regional trainers add $1.8M. Together, that is about $6M against a previous profit of roughly $10M — explaining most of the 18% drop.
Step 4: Recommendation
Negotiate volume pricing with the new supplier or blend premium beans with the previous supplier for core menu items. Consolidate regional trainers into a smaller centralized team. Consider a small price increase on specialty drinks where customers are less price-sensitive.
What interviewers are looking for
They want to see you move methodically from structure to data to recommendation. The worst thing you can do is guess. The second worst is lay out a framework and then ignore it. Follow your own structure.
2. Market entry case: TechNova in Southeast Asia
The prompt
TechNova is a US-based B2B SaaS company that sells project management software to mid-size companies. They have $80M in US revenue and want to expand into Southeast Asia. Should they do it, and how?
How to structure this
Market entry cases need four questions answered: Is the market attractive? Can we win? How do we enter? Is it worth the investment? Take them in order.
Walkthrough
Step 1: Market attractiveness
Southeast Asia's B2B SaaS market is growing at roughly 25% per year. Indonesia, Vietnam, and the Philippines have a fast-growing segment of mid-size companies adopting cloud tools. However, average contract values are 40-60% lower than the US.
Step 2: Competitive landscape
Local competitors exist but lack TechNova's feature depth. Global players (Asana, Monday.com) have limited localization. TechNova's advantage is strong if they invest in local-language support and regional pricing.
Step 3: Entry mode
Three options: organic (build a local team), partnership (reseller network), or acquisition. Given low brand awareness and cultural differences, a partnership with established IT distributors is the lowest-risk starting point. Organic expansion can follow once they have reference customers.
Step 4: Financial case
With a $3M investment over 18 months and projected revenue of $5M in year two (based on 200 mid-size customers at $25K average contract value), breakeven happens around month 20. Worth doing if TechNova has the cash and the patience.
Common mistake
Candidates often spend all their time on "is the market big?" and never get to "can we actually win there?" Size doesn't matter if you can't compete. Make sure you cover both.
3. Market sizing case: EV charging stations in the US
The prompt
How many public EV charging stations will the US need by 2030?
How to structure this
Market sizing is about building a logical estimate from reasonable assumptions. Nobody expects your number to be exact. They want to see how you think through it.
Walkthrough
Step 1: Estimate EVs on the road by 2030
The US has roughly 290 million registered vehicles. Current EV share is about 4%. With current growth rates, a reasonable estimate for 2030 is 15-20% EV share. Call it 50 million EVs.
Step 2: How many need public charging?
About 80% of EV charging happens at home. But roughly 30% of US households lack home charging access (apartments, street parking). For those 15 million EV owners, public charging is the primary option. Add the road-trip and top-up demand from the other 35 million.
Step 3: Charging sessions per station per day
A Level 2 charger takes 4-6 hours. A DC fast charger takes 20-40 minutes. Assume a mix: a typical station serves 8-12 sessions per day. To handle peak demand, target 70% average utilization.
Step 4: Back into the number
If 15 million primary public chargers need roughly 2 sessions per week, that is 30 million weekly sessions, or about 4.3 million daily. At 8 sessions per station per day, you need about 540,000 charging stations. Add a 20% buffer for geographic coverage (rural areas, highways), and you land around 650,000.
Why this works
The actual number doesn't need to be right. What matters is that each assumption is stated clearly, and the logic flows from one step to the next. If the interviewer pushes back on an assumption, you adjust that number and recalculate.
4. M&A case: PharmaCo acquires a biotech startup
The prompt
PharmaCo is a large pharmaceutical company with $20B in annual revenue. Their blockbuster drug loses patent protection in 2028. They are considering acquiring GeneVia, a biotech startup with a promising gene therapy platform in Phase 2 trials. Should they do the deal?
How to structure this
M&A cases come down to three questions: Does the target make strategic sense? What is it worth? What are the risks? Don't skip any of them.
Walkthrough
Step 1: Strategic fit
PharmaCo needs pipeline replacement before 2028. GeneVia's gene therapy platform addresses rare diseases with limited competition and high pricing power. It fills a gap that internal R&D hasn't solved. Strategic fit is strong.
Step 2: Valuation
GeneVia has no revenue yet. Value it on potential: if the gene therapy platform gets FDA approval (assume 60% probability for Phase 2), the addressable market is roughly $3B. With 20% market share and 70% gross margins, peak annual revenue would be around $600M. Apply a risk-adjusted DCF: the business is worth roughly $2-3B.
Step 3: Risks
Phase 2 to approval has a 30-40% failure rate in biotech. Integration of a small biotech into a large pharma company often kills the culture that produced the innovation. GeneVia's key scientists might leave.
Step 4: Recommendation
Pursue the deal, but structure it to manage risk. Pay $1.5B upfront with $1.5B in milestone payments tied to FDA approval and commercial targets. Keep GeneVia as a semi-autonomous unit to retain talent and culture. This limits downside while securing the pipeline PharmaCo needs.
What separates good from great here
Weak candidates say "yes, buy them." Good candidates quantify the value. Great candidates address the risks and structure the deal to mitigate them. The interviewer wants to see you think about downside, not just upside.
How to get better at case interviews
Reading examples helps, but reading is not practice. Case interviews are a performance skill — you get better by doing them repeatedly under pressure.
CaseXcel gives you daily case drills, mental math exercises, and framework practice in your phone. Short sessions, adaptive difficulty, and progress tracking that shows where you are weak so you can fix it.
If you are preparing for McKinsey, BCG, Bain, Deloitte, or any other consulting firm, consistent daily practice is what separates the candidates who get offers from the ones who almost did.