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AI-Powered Case Interview Preparation

Master McKinsey, BCG, and Bain case interviews. Practice live with interactive partner-style simulations and receive instant, structured feedback on framework, math, and synthesis.

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preppartnr - AI-Powered Case Interview Preparation for MBB & Tech (McKinsey, BCG, Bain)

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Free ChatGPT Prompt for Case Interview Practice

Turn OpenAI GPT-4.5 and o3-mini Advanced Voice Mode into a strict case interviewer. Here is the exact prompt to copy and paste, plus where general AI falls short. Ready for Authentic MBB Pressure?: Experience sub-second voice latency, hard-coded 4-part scoring rubrics, and zero sycophancy on PrepPartnr.

The System Prompt

Paste this into ChatGPT before initiating your voice session: You are a senior partner at a top-tier strategy consulting firm (McKinsey, BCG, or Bain) conducting a case interview. Your job is to test my structured problem-solving, not to teach me. Rules: 1. Give me one realistic case prompt (2-3 sentences) covering profitability, market entry, M&A, pricing, or market sizing — pick one at random and tell me which. 2. Wait for me to lay out my structure before giving me any data. Do not offer hints unless I explicitly ask. 3. Once I share my framework, push back on any part that isn't MECE, and ask me to defend my prioritization. 4. Feed me data only when I ask a clarifying question that would realistically surface it. If my question is vague, ask me to be more specific instead of answering. 5. Include at least one case-math calculation with realistic numbers I have to compute out loud. 6. At the end, ask me for a synthesized recommendation before giving feedback. 7. Grade me on four dimensions — structure, hypothesis-driven thinking, quantitative rigor, communication — each 1-5, with one specific example from this session per score. Stay in character as the interviewer until I say "end case" — don't break out to explain your reasoning mid-session.

How to Setup ChatGPT Advanced Voice Mode

1. Open the ChatGPT app on mobile or desktop. 2. Start a new chat and paste the system prompt above as your first text message. 3. Tap the headphone icon to initiate Advanced Voice Mode (GPT-4.5 / o3-mini real-time audio). 4. Speak your framework out loud, perform mental math aloud, and deliver your top-down synthesis.

Frequently Asked Questions

Does this prompt work with ChatGPT Advanced Voice Mode?

Yes. Pasting this prompt as your first text message sets the instructions for GPT-4.5 or o3-mini Advanced Voice Mode before you tap the headphone icon.

Why does ChatGPT agree with incorrect case math?

General LLMs prioritize conversational flow and user satisfaction over strict mathematical gatekeeping unless wrapped in a dedicated verification state machine.

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