McKinsey Solve in 2026: the games, the rules and a fair way to prepare

What is McKinsey Solve in 2026?

Solve is a gamified online assessment that McKinsey sends to most consulting applicants, usually before any interviewer has spoken to them. McKinsey's own description is short: a gamified step in its recruitment process that assesses your problem-solving abilities, to be approached "with curiosity and creativity", with your performance "considered in conjunction with the rest of your application and any other assessments you are asked to take". We read that wording on mckinsey.com on 29 September 2026.

The history is worth two sentences because it explains the design. McKinsey says it began working with the start-up Imbellus in 2016 to replace an in-person pen-and-paper multiple-choice test, piloted the game with 500 people in London in November 2017, and had an online version ready in autumn 2019. The idea, in McKinsey's words from a May 2020 careers post, was to set tasks rather than pose questions, on the theory that watching how someone works through a task shows how they approach problems more generally.

Here is what the official pages leave out: which games exist, how long each takes, how the score is built, what a passing score is. Everything below about specific modules therefore comes from candidate reports (PrepLounge threads from 2026, mostly) and from prep vendors, and we label it as such. Where those sources disagree with each other, and they do, we say so and do not pick a winner.

A few practical facts do come from McKinsey, from the Solve FAQ (the August 2025 edition). Every task begins with an untimed tutorial. The length of your assessment is in your invitation email. Solve runs on a PC or Mac only, so no iPad or phone, and sound is not necessary and a mouse is optional. You can take it in English, Spanish (Iberia or Latin America), Portuguese (Iberia or Latin America) or Japanese.

Which Solve games are live, and which are retired?

Names first, because the spelling confuses people. Redrock, Red Rock, Redrock Island and Redrock Study all refer to the same module in candidate reports. Sea Wolf is sometimes called the ocean treatment or ocean clean-up game. Sustainable Futures Lab is often shortened to SFL, and you will also see it written as Sustainable Future Lab.

As of 29 September 2026, and from candidate reports only, two modules make up the default sequence and a third appears for some candidates. The tabs below give what each one looks like, what it appears to test, the reported time and the mistakes we would expect. Treat the descriptions as a briefing on what people say, not as a specification.

The disagreement on SFL is a useful warning about the whole genre. One vendor says the module arrived in March 2026, another says 2025, a coach on a June 2026 forum thread called it a 15 to 20 minute situational judgement test, and a September post says the 20-minute version has already been replaced. All of them cannot be right at the same time, and probably several were right at different times. Everyone writing about Solve, us included, is working from candidates who remember a session they were told not to share.

That last point deserves a moment. McKinsey's integrity page asks candidates to refrain from sharing the content of their assessment, including specific questions and scenarios. The consequence for anyone hoping to find the exact questions online is that most of what is posted is either vague or from an older version. Read accordingly.

How long is Solve, and does it differ by role or region?

McKinsey's answer is that the length is in your invitation email, which is the whole of the official position. Candidates report several lengths, and the mapping from role or office to length is not published anywhere we could find. One vendor states that role and region decide it. We could verify only that a candidate applying as a junior associate in Paris reported an 85-minute invitation with three modules in a June 2026 PrepLounge thread.

Two consequences for how you plan. The tutorials are untimed, so the stated length may not include them, and the FAQ does not say. Book a slot with at least 30 minutes of margin beyond the stated length, and do the tech check well before the day. And do not assume a friend at another office, or in a different cycle, sat the same thing. McKinsey's FAQ also says Solve varies the parameters so that no two candidates share the same data, which is one more reason comparing answers is pointless.

How is McKinsey Solve scored?

Nobody outside McKinsey knows the scoring model, and that includes every vendor selling a simulator. What can be said sorts into three piles: things McKinsey has stated, things candidates and vendors repeat without McKinsey confirming them, and things that are speculation. Keeping the piles apart is most of the skill in reading anything about Solve.

Our reading, and it is a reading: assume that both the quality of your answers and the way you got there are looked at, and behave as if someone is following your method. In practice that means reading the objective before you touch anything, committing to an approach, checking before you submit, and not clicking around to see what happens. That advice is good under every scoring model anyone has proposed, which is the only reason we are comfortable giving it.

You will also see figures such as "80% of candidates fail" or "one in five pass without preparing". We found no source for any of them. McKinsey publishes no pass rate, and the people quoting one have no way of observing it. Ignore them, and be a little suspicious of whoever is selling you a course on the strength of them.

Is Solve proctored, and can you use a calculator, Excel or ChatGPT?

Three McKinsey documents bear on this, and the accurate answer comes from reading them together. We read all three on 29 September 2026. McKinsey can change the wording at any time, so read them again before your own session.

• The Solve page: except for an accommodation approved in writing, you are not permitted to "use applications, websites, AI tools, or pre-prepared notes" or to "record or capture screenshots of any part of the assessment", and you are expected to take it alone. The listed consequences are "exclusion from consideration, rescinding of an offer, restrictions on future applications, or legal action"
• The Assessment Integrity Expectations page, which covers "any assessment or interview, including those done virtually": participate alone, use one screen without overlays, be on camera with virtual backgrounds and blurring off, position the camera to show your full upper body and hands "as you take notes and perform calculations", use only pen and paper for notes and calculations, and discard the notes afterwards. It also asks you to refrain from using "any applications or websites, generative AI, a calculator, or prepared notes" and from sharing information about the content of the assessment with others
• The careers FAQ under interviewing: no external apps, websites, calculators or pre-prepared notes, alone and on one screen, and no generative AI to "craft real-time responses". The same FAQ describes using AI to prepare as understandable, much as candidates once asked family and friends for help

Put together, the written answers are these. No ChatGPT or any other AI during the assessment. No Excel, no browser, no phone calculator. No second screen. Notes on paper only, and destroyed afterwards. McKinsey's interviewing page sorts the AI question the same way: practising interview questions with AI is encouraged, and using AI during assessments unless specifically permitted is not allowed.

Two points stay open. First, whether the game itself offers an on-screen calculator. Some prep sites describe one in Redrock, McKinsey's public pages do not mention it either way, and the untimed tutorial at the start of each task is where you would find out. Second, the camera. The integrity page says on camera for any assessment, while the Solve page and FAQ mention neither webcam nor proctor, and the FAQ says only that a tech check confirms your device meets minimum requirements. One prep site states flatly that Solve involves no webcam monitoring. We could not verify that and would not rely on it. Set up as if you are on camera. It costs nothing.

The FAQ also says you may be asked at random to take an additional task in person, or to explain the logic you used. That is one more reason to work in a way you could describe afterwards.

What does Redrock ask, and how do you get faster at the maths?

Redrock is where case practice pays off most directly, so it gets a worked example. The exercise below is ours, written for this guide, with invented numbers and an invented setting. It is not content from Solve. It has the shape candidates describe: a few figures, some percentages, and a question that rewards noticing what the totals hide. Try it on paper before opening the answer, and give yourself three minutes.

Look at how the answer is built. The order is fixed: last year's base, then this year's figure, then the change, then the split by part, then an explanation of the gap between two growth rates. The weighted-average check at the end is the sense-check that costs ten seconds and catches the commonest error, which is averaging the three growth rates (8, -10 and 15 average to 4.3%) and stopping.

The quiz has a built-in sense-check, and it is the one to steal. The answer has to lie between 60% and 80%, and nearer 80% because the bigger zone recycles more. Two seconds on that before calculating rules out 68% and makes 70% look suspicious. Here is the version of that habit we mark in interviews, with the published anchors from our own rubric. It is our case-interview rubric, not McKinsey's Solve marking, and we show it because the behaviour transfers.

If percentage change, weighted averages and base-year traps still feel slow, the fix is the drill set in our case interview maths guide, done on paper against a clock. Redrock has no interviewer to notice a slip, so the checking has to be yours.

Where does Solve sit in the McKinsey process?

Before the interviews. McKinsey's interviewing page says that for most client-facing roles you have a personal experience interview followed by a problem-solving interview, and that Solve is a step in the process for most consulting roles. Which step, in which order, and how many rounds follow depends on office and role, and your recruiter confirms the details. Candidate reports vary on whether the Solve invitation arrives before or after an initial recruiter call.

The reason to keep this sequence in mind is that Solve is over in an hour or so and the case interviews are not. Solve tests nothing you say aloud, and the interviews test almost nothing else. Our McKinsey case interview guide covers what the interviewer-led problem-solving round looks like, and the McKinsey PEI guide covers the behavioural half, which many candidates underprepare because Solve absorbed their attention.

How long do results take, and can you retake Solve?

McKinsey publishes no results timeline for Solve. Its careers FAQ says the recruitment process differs by role and location and that your recruiter will share the approximate timing of each step. Candidate reports are what we have. Coaches answering a PrepLounge thread in January 2026 said one to two weeks, and one to three, are typical. Those are opinions from a forum, and offices and cycles differ.

What does silence mean? Usually a queue, and occasionally nothing at all. Because McKinsey says Solve is weighed with the rest of your application, a result can sit while a recruiter reviews a batch of applications. We would treat two weeks with no word as the point to send one short, polite email to your recruiter, and we would not read a rejection into a shorter wait.

Retakes are the least documented part. The reports do not agree, and McKinsey's pages we read state no policy. In a July 2024 PrepLounge thread, two coaches said a Solve result is typically valid for 12 months and that a 12-month wait after an unsuccessful application is usual, while the original poster said a recruiter had mentioned applying for a full-time role within three months. Another vendor says 12 to 24 months. Our advice is to ask your recruiter directly what applies to your office and role, and to do it before you reapply rather than after.

One thing is official. If something breaks during Solve, the FAQ says to contact support at the moment it happens, at gbil-support@mckinsey.com or through live chat, and that support can offer extra time or reset your link depending on the issue. It also says that if you have a technical problem and do not contact support, no exception can be made for a reset. So the rule is to write to them then, not afterwards, and contacting them does not cost you time.

How should you prepare, and what transfers from case practice?

McKinsey says there is no need to prepare, and describes Solve as needing no previous business knowledge or gaming experience. We think that is true of the mechanics, which the tutorials teach, and only half true of the experience. Redrock is 35 minutes of timed arithmetic and chart reading. Someone who has not calculated a percentage change since university will lose marks to slips that preparation would have removed, so we prepare the maths and the calm, not the game.

On third-party simulators, be fair to them and cautious. They are unofficial, McKinsey does not review or endorse them, and the modules have changed by candidate accounts more than once, so a simulator built for last year's version can teach the wrong shape. Some are useful for seeing an interface before it counts. We would spend two or three hours on one, treat it as familiarisation, and never pay for one that promises to predict your score, because nobody outside McKinsey has the model needed to make that promise. McKinsey's own material is thinner than any of them: the Solve page carries a video on what it feels like to play, and each task opens with a tutorial.

The table also explains a common frustration. Candidates who have practised thirty cases arrive at Solve and find that most of what they built is beside the point, while the one thing that carried over, quick and accurate arithmetic, was the part they had practised least. If you are early in your preparation, our case interview preparation guide puts the maths where it belongs in the overall plan.

What is a realistic one-to-two-week plan, and what should you do on the day?

Two weeks is comfortable and one week is workable if you skip step four. The plan assumes you are also preparing for the interviews, which are the larger prize, so Solve gets about 45 minutes a day and no more.

On the day itself, most problems come from the setup and not from the game. The checklist below is built from McKinsey's written rules and its FAQ, and it is worth going through the evening before as well as an hour before.

One more note for people applying to more than one firm. Bain and BCG run their own online assessments, with their own rules and formats, and nothing here applies to them. Our guides on the BCG online case and the Bain online assessment cover those separately.