GuidesUpdated 1 November 2026
The Oxford Computer Science interview
Oxford Computer Science interviews are held by video call in December. Shortlisted applicants usually have two interviews at their first-choice college and at least one at another, each around 30 minutes with two interviewers, and most of the time goes on solving a problem out loud.
Shortlisting uses the TMUA, which replaced Oxford's own MAT for the 2026 admissions round. The department publishes sample interview problems, and its advice is blunt: "Our tutors are not mind readers", so talk through your thinking. Here is the format, the published problems, a worked example and how to prepare.
How does the Oxford Computer Science interview work?
| Question | What the department says |
|---|---|
| Admissions test | TMUA (Test of Mathematics for University Admission), no pass mark. The MAT ran from 2007 to 2025 and won't take place in the 2026 round |
| When | December, by video call |
| How many interviews | Usually two at your first-choice college and at least one at another college |
| Length | Around 30 minutes each, usually with two interviewers |
| Content | Mostly a computer science problem you work through out loud, like a short tutorial |
| Joint degrees | Single-subject interviews for each part, or one with tutors from both subjects |
| Competition | 21% of applicants interviewed, 7% successful, intake 55 (2023-25 average) |
| Decisions | January |
The department adds that you don't need special training: the main thing is to do lots of mathematics and find it interesting. Its advice is all about mathematics: none of the published problems needs programming.
Sample problems the department has published
Oxford's Department of Computer Science lists problems "that have been used in interviews in the past". In its own words, they include:
| Problem | What it asks (summarised) | The skill it tests |
|---|---|---|
| Tidy boxes | Pack 100 blocks of 10 colours into 10 boxes of 10 so each box has at most two colours | Proof by construction |
| Searching for the maximum | Find where a function with a single maximum peaks, asking for as few values as possible | Search strategy, efficiency |
| Death by chocolate | A take-turns game with one poisoned square: go first or second? | Game strategy, invariants |
| Monkey beans | 23 white and 34 black beans, a rule for replacing pairs: what colour is left? | Spotting an invariant |
| Lily-pad lunacy | How many ways can a frog jump from pad 0 to pad 10 in ones and twos? | Recursion, counting |
| Missing numbers | Find a number missing from a list of almost a million | Algorithms, efficiency |
| Scribble | Which words can be made from PQ under three rewriting rules? | Formal systems, invariants |
The University's sample interview questions page adds one more, from a Computer Science tutor: "How do pirates divide their treasure?" Seven ruthless, perfectly logical pirates split 100 coins under voting rules. The tutor says the way in is to look at what happens with only two pirates and work up, and that he's watching how you take directions and break a problem into smaller parts (source: University of Oxford, sample interview questions).
A worked example: Lily-pad lunacy
The published problem: a frog on pad 0 wants to reach pad 10, jumping forward one or two pads at a time. How many different ways are there? (Source: Oxford Department of Computer Science sample interview problems.)
- What a strong answer does: starts tiny. How many ways to reach pad 1? Pad 2? Pad 3? It says each count out loud and looks for a pattern.
- The key move: notices that the last jump into any pad is either a one or a two, so the ways to reach a pad come from the two pads before it. Then it says why that's true, not just that the numbers fit.
- Weak answer: trying to list all the routes to pad 10 by hand, in silence.
- What usually comes next: a twist, such as "What if the frog can also jump three pads?" or "What if pad 5 is missing?", to see if you can adapt the idea.
What about Cambridge Computer Science?
Cambridge also requires the TMUA for Computer Science, and applicants to Peterhouse or Trinity also take the Computer Sciences Aptitude Test (CSAT). In the 2025 cycle Cambridge reported 14 applications per place and 128 students accepted. Interviews follow the Cambridge pattern: usually one or two in December, often with a problem to work through and share. See what to expect at a Cambridge interview.
How to prepare
- Work the published problems out loud. Try each one for 20 minutes, speaking every step, before you look anything up.
- Practise the opening moves. Small cases, a table, a simpler version of the problem. Tutors want to see a sensible start.
- Get used to hints. In a real interview the tutor nudges you. Practise taking a hint and running with it instead of starting over.
- Revise your school maths. Induction, sequences, basic probability and proof are the tools most problems use.
- Prepare a short "why computer science". Most time goes on problems, but you may be asked why the subject and what you've explored.
AdmitMock is an AI mock interview app for Oxford, Cambridge, Imperial, UCL and US college alumni interviews: an AI interviewer asks the questions out loud, follows up, and shows you what to fix.
Frequently asked questions
Do I need to know how to code for the Oxford Computer Science interview?
No. The interview problems use school mathematics and logical thinking. The department says you don't need special training.
What admissions test does Oxford Computer Science use?
The TMUA. Oxford's own MAT ran from 2007 to 2025 and was replaced by the TMUA for the 2026 admissions round. There is no pass mark.
How many interviews are there for Oxford Computer Science?
Usually two at your first-choice college and at least one at another college, each around 30 minutes.
Are Oxford Computer Science interviews online?
Yes. They happen in December by video call.
What if I get stuck in the interview?
Keep talking. Say what you've tried and why it didn't work. Tutors expect to give hints, and how you use them is part of what they see.
Related guides
Sources
Checked 1 November 2026.
AdmitMock is not affiliated with the University of Oxford, the University of Cambridge or any of their colleges. We use published formats and questions, not insider information.
