How to Beat McKinsey Solve: A Step-by-Step Guide

McKinsey Solve is the gamified pre-interview assessment every McKinsey candidate has to pass before getting a case interview. Roughly 60-75 minutes long, two mini-games, and a pass/fail score that McKinsey has never published the exact threshold for. The game is designed to test the same problem-solving instincts that the case interview tests, in a setting that's harder to prep for than a traditional aptitude test.

I went through McKinsey recruiting before Solve replaced the old Problem Solving Test (PST), and I've watched dozens of WSG candidates take Solve in the last three cycles. The pattern is consistent: candidates who treat Solve as a logic test fail. Candidates who treat it as a case interview in game form pass at materially higher rates. This guide breaks down what Solve actually tests and how to prepare for the 2026 cycle. [VERIFY: confirm Solve format hasn't changed on mckinsey.com/careers]

What is McKinsey Solve?

McKinsey Solve (sometimes called the McKinsey Imbellus, the McKinsey Digital Assessment, or just the Solve game) is the gamified screening assessment used by McKinsey globally for Business Analyst, Associate, and most experienced-hire roles. Candidates get the Solve invitation after submitting an application, and they typically have one to two weeks to complete it.

The game has two scenarios: Ecosystem and Redrock. Both are set in nature-themed environments (a coral reef, a wolf colony) but the underlying skills tested are business problem-solving skills disguised as ecology problems.

How long does McKinsey Solve take and is it timed?

Total runtime is roughly 60-75 minutes for both games combined. Each game has a hard time limit displayed on screen as a countdown. You cannot pause, you cannot retake, and you cannot return to a question once you've moved on. The single take is the single submission.

McKinsey recommends finding a quiet 90-minute block, using a laptop (not a phone or tablet), and treating it as a real interview event. Candidates who attempt it on a tight schedule or in a noisy environment consistently underperform.

The Ecosystem game (build a sustainable food chain)

What it looks like: You see a 3D environment (a coral reef or mountain plateau) and a list of species. You must build a food chain that sustains itself over multiple cycles, picking species based on their food requirements, predators, and environmental fit.

What it actually tests:

• Constraint satisfaction. You have to satisfy multiple constraints simultaneously (calories, predator-prey relationships, terrain fit).

• Quantitative reasoning. Each species has numeric parameters. You have to do quick math on food intake vs availability.

• Trade-off analysis. Adding one species often pushes another out. You have to read the second-order consequences.

  
  

The McKinsey-style insight: the game rewards candidates who pick species that fill the most constraints with the fewest resources. This is the same instinct that a McKinsey BA uses when prioritizing client recommendations under capital constraints. Solve isn't testing whether you can do ecology. It's testing whether you can spot the highest-leverage move under pressure.

The Redrock game (analyze data and answer questions)

What it looks like: You see a scenario (a wolf colony, a bird migration study) with a data dashboard, charts, and a set of questions to answer about the data. The questions get progressively more analytical: count items, calculate averages, identify patterns, make recommendations.

What it actually tests:

• Quantitative speed. You have to do calculations quickly without a calculator (Solve provides an on-screen calculator but the time pressure is real).

• Chart reading. Identifying patterns from bar charts, line charts, and scatter plots.

• Inference under uncertainty. Some questions ask you to project from incomplete data.

  
  

The Redrock game maps almost perfectly onto the quantitative portion of a McKinsey case interview. If you can do mental math at speed and read a chart accurately, you'll pass the quantitative section.

How is McKinsey Solve scored?

McKinsey does not publish the scoring algorithm or the pass threshold. Solve has been reverse-engineered by third-party prep sites, and the consensus is that the scoring weighs three dimensions:

• Process score. How you played, not just the final answer. The game tracks every move, every backtrack, every selection.

• Outcome score. Did your food chain survive? Did you answer the analytical questions correctly?

• Time-management score. Did you use the available time efficiently or did you spend 20 minutes on one question?

  
  

The implication for prep is important. You cannot brute-force Solve by memorizing the right answers. The game tracks your decision process and a candidate who reached the right answer by trial-and-error scores worse than a candidate who reached it through deliberate reasoning. Treat every move in the game as if McKinsey is watching how you think, because they are.

Four prep mistakes that fail Solve

Mistake 1: Treating it as a logic puzzle

Candidates who watch YouTube videos of "Solve answers" and try to memorize patterns consistently fail. McKinsey rotates scenarios. The food chain you build in your prep video isn't the food chain the live game gives you. Stop chasing answers. Start practicing reasoning under time pressure.

Mistake 2: Skipping the math drilling

The Redrock game has a quantitative section that rewards mental math at speed. Candidates who can multiply two-digit numbers, calculate percentages, and read a chart in under 10 seconds finish the game with time to spare. Candidates who can't are still stuck on question 4 when the timer runs out.

Drill mental math separately. Khan Academy basic arithmetic, GMAT quant flashcards, or the standard "mental math under 30 seconds" exercises in any case prep book. Do 20 minutes a day for two weeks before Solve.

Mistake 3: Doing Solve on a poor setup

This is the single most preventable failure mode. A laptop with a small screen, a slow internet connection, or a noisy environment will cost you the game. Use a desktop or large laptop, wired internet if possible, and a closed-door room. Tell roommates not to interrupt for 90 minutes.

Mistake 4: Treating Solve as separate from the case interview

Solve and the case interview test the same underlying skills. Candidates who prep heavily for Solve but skip case interview reps end up passing Solve and then failing the case round two weeks later. The skills that win Solve are the skills that win the case interview. Prep for both as one integrated process.

What changed about Solve in 2026

McKinsey has iterated Solve multiple times since the original Imbellus launch in 2017. The 2026 version is the most refined to date. Three specific changes worth knowing:

The game has gotten more pattern-resistant. Earlier versions of Solve had reusable patterns (the same predator types, the same chart formats) that candidates could memorize from third-party walkthroughs. The 2026 version randomizes the scenarios more aggressively, which makes memorization-based prep almost useless.

The Redrock data analytics section has gotten harder. McKinsey added more multi-step questions where you have to combine information from two charts or two data tables before answering. This rewards candidates who can hold multiple data points in working memory at once, not just candidates who can read a single chart.

The time pressure has eased slightly. The total runtime is still 60-75 minutes but the per-question time allowances have been adjusted so that careful candidates can finish within the limit. The intent is to test reasoning, not raw speed.

The takeaway: prep methods that worked in 2022 or 2023 are increasingly obsolete. Use 2025-2026 prep materials only, and don't rely on YouTube videos from before the 2024 refresh. [VERIFY: confirm 2026 Solve mechanics with McKinsey directly]

A two-week prep plan that actually works

This is the plan I'd give a sophomore who just got their Solve invitation and has two weeks to prepare. Total time commitment: 15-20 hours.

Week 1: foundation

• Day 1-2: Read the McKinsey Solve overview on the McKinsey careers page. Watch one full unofficial walkthrough of Ecosystem and one of Redrock on YouTube. You're calibrating expectations, not memorizing.

• Day 3-4: Mental math drills, 30 minutes per day. Multiplication, percentages, ratios, chart reading. Use the GMAT quant prep app or any free math drill site.

• Day 5-7: Take one full McKinsey case interview practice case from the McKinsey case prep page. Solve and the case interview test the same skills, and the case practice strengthens both.

  
  

Week 2: simulation

• Day 8-10: Run a simulated Solve under timed conditions using a third-party simulator (PrepLounge, IGotAnOffer, MyConsultingOffer all offer Solve simulations). Take the score with a grain of salt. The point is exposure to the format under pressure, not the score itself.

• Day 11-12: Drill Ecosystem-style constraint satisfaction. Set up a simple resource allocation problem on paper and solve it in 5 minutes. The skill being practiced is recognizing the highest-leverage move under multiple constraints.

• Day 13: Rest day. Don't drill the day before Solve. Sleep and eat well.

• Day 14: Take the live Solve in a closed-door room with a stable internet connection.

  
  

What McKinsey is actually looking for in Solve

The honest answer that McKinsey will never officially give you: Solve is a behavioral test in disguise. They don't care if you remember every food chain species. They care if you make decisions like a McKinsey BA would.

A McKinsey BA who reaches a partner-level meeting and is asked "what would you do?" needs to (a) identify the constraints, (b) prioritize by leverage, (c) execute under time pressure, (d) defend the reasoning. Solve tests every one of those in game form.

The candidates who think of Solve as a McKinsey-style decision exercise pass at higher rates than candidates who think of it as a video game. The framing changes everything about how you approach each move.

When I was at McKinsey, the partners I worked with all shared a specific kind of thinking pattern. They would walk into a meeting, identify the two or three things that actually mattered, and ignore the noise. Solve is the closest McKinsey can get to testing that pattern in a 75-minute online assessment. The candidates who consistently fail Solve are usually the ones who get sucked into optimizing every variable instead of identifying the few variables that drive the outcome.

Frequently asked questions

Can I retake McKinsey Solve if I fail?

No. McKinsey policy is one attempt per cycle. If you fail Solve, you typically cannot reapply to McKinsey for 12-24 months.

Do BCG and Bain use Solve?

No. BCG has its own assessment called Casey (chatbot-based) and Bain uses either the Bain Online Test (BOT) or the Pymetrics behavioral game depending on the office. Solve is McKinsey-only.

Is Solve different for experienced hires?

The structure is the same. The bar may be slightly different. Experienced hires who fail Solve get cut just as undergrads do.

Does Solve have practice mode?

McKinsey provides a brief tutorial within the live Solve interface. There is no official practice mode. Third-party simulators exist but they are approximate, not exact replicas.

The honest final read

McKinsey Solve is harder than the old PST and easier than a final-round case interview. A well-prepared candidate with two weeks of focused prep, decent math fluency, and a good test setup passes at roughly 60-70% rates. A candidate who walks in cold passes at materially lower rates.

The single best thing you can do is treat Solve as if a McKinsey partner is watching every click. The single worst thing you can do is treat it as a video game you can game.

You don't beat Solve. You demonstrate that you already think the way a McKinsey BA thinks. The prep is just teaching your hands to keep up with your brain under pressure.

Stephen Turban is the co-founder of Wall Street Guide and Lumiere Education. He graduated Magna Cum Laude from Harvard College in Statistics, worked as an Business Analytics Fellow at McKinsey & Company. He founded WSG to give ambitious students the same insider access to finance and consulting recruiting that top-school students take for granted.