How to Prepare for a McKinsey Interview: A Complete Guide
Learn the insider strategies for acing your McKinsey interview. From case studies to fit questions, we cover everything you need to know to land your offer.
Cut to the Case Team
January 15, 2025
Introduction
Landing a McKinsey interview is a significant achievement, but it's just the beginning. The real challenge lies in the preparation. As a former McKinsey interviewer who conducted over 100 interviews, I've seen candidates succeed and fail—and I know exactly what separates them.
The Two Parts of a McKinsey Interview
Every McKinsey interview consists of two main components:
1. The Fit Interview (Personal Experience Interview)
McKinsey calls this the "Personal Experience Interview" or PEI. Don't let the casual name fool you—this is not a casual conversation. You'll be asked to share specific stories that demonstrate key leadership competencies:
- Entrepreneurial Drive: Times you created something from nothing
- Inclusive Leadership: How you brought people together
- Personal Impact: Moments where you made a measurable difference
- Problem Solving: Situations where you navigated ambiguity
Pro Tip: Prepare 4-5 strong stories that you can adapt to different questions. Each story should follow the STAR format (Situation, Task, Action, Result) but focus heavily on the "Action" portion.
2. The Case Interview
The case interview is McKinsey's signature assessment. You'll be presented with a business problem and asked to work through it with your interviewer.
Common Case Types:
- Profitability cases - "Our client's profits have declined 20%. Why?"
- Market entry - "Should our client enter the electric vehicle market?"
- M&A - "Should our client acquire this competitor?"
- Operations - "How can we reduce manufacturing costs by 15%?"
Key Preparation Strategies
Structure is Everything
McKinsey interviewers are looking for structured thinking. When you receive a case, take 30-60 seconds to organize your thoughts before diving in. Use a hypothesis-driven approach:
- Restate the problem
- Form an initial hypothesis
- Present a structured approach to test your hypothesis
- Work through the analysis methodically
Practice Mental Math
You will do math in McKinsey interviews. Period. Get comfortable with:
- Percentages and percentage changes
- Basic multiplication and division
- Market sizing calculations
- Growth rates and compound growth
Master the Synthesis
At the end of every case, you'll need to synthesize your findings into a recommendation. Practice the "Pyramid Principle":
- Lead with your recommendation
- Support with 2-3 key reasons
- Back each reason with evidence from your analysis
Timeline for Preparation
| Weeks Before | Focus Area |
|---|---|
| 8-6 weeks | Learn frameworks, start casing with partners |
| 6-4 weeks | Intensive practice (2-3 cases daily) |
| 4-2 weeks | Focus on weak areas, mock interviews |
| Final 2 weeks | Light practice, mental preparation |
Common Mistakes to Avoid
- Memorizing frameworks - Interviewers can tell when you're forcing a framework. Instead, understand the underlying logic.
- Rushing into the case - Take time to structure. Silence is okay.
- Ignoring the interviewer - This is a conversation, not a presentation. Engage with your interviewer.
- Weak math - Practice until mental math is second nature.
- No synthesis - Always end with a clear recommendation, even if you're unsure.
Final Thoughts
McKinsey interviews are challenging, but they're also incredibly predictable. The firm values structured thinking, intellectual curiosity, and clear communication. Master these, and you'll be well on your way to an offer.
Want to learn more? Our CaseMap™ Methodology breaks down exactly how to approach every aspect of the McKinsey interview process.