IB Computer Science is one of the most practical and future-focused subjects in the International Baccalaureate (IB) Diploma Programme (DP). The IB has introduced a new course, first taught in August 2025, with first exams in May 2027. This guide explains what the new course involves, how it is assessed, what has changed and how to succeed.
Which course are you on?
- If your first IB Computer Science exams are in May 2027 or later, you are studying the new course described in this guide.
- If you are sitting exams in November 2026, you are on the previous course, which has its last assessment in 2026. See our November 2026 exam schedule for your paper dates.
Key Takeaways
- The course has two themes: Theme A, Concepts of computer science, and Theme B, Computational thinking and problem-solving (IB, 2024).
- You study and answer programming questions in either Java or Python.
- Assessment is two exam papers plus the internal assessment (IA), a computational solution worth 30% at Standard Level (SL) and 20% at Higher Level (HL).
- Paper 3 and the option topics have been removed. The case study is now part of Paper 1, for both SL and HL students.
- Machine learning is now a core topic for every student.
Course Structure
IB Computer Science is offered at Standard Level (SL) and Higher Level (HL). The IB recommends 150 teaching hours at SL and 240 hours at HL. HL students study the same topics as SL students, plus extra depth and one HL-only topic.
Computer Science is a group 4 science in the Diploma Programme, alongside subjects such as Biology, Chemistry and Physics. This means it can be your science subject.
The course is organised into two themes. According to the IB, Theme A focuses on how computing systems work, and Theme B focuses on how we use computing systems to solve real-world problems. A case study, the internal assessment and the collaborative sciences project complete the course.
Teaching Hours
| Component | SL hours | HL hours |
|---|---|---|
| Theme A: Concepts of computer science | ||
| A.1 Computer fundamentals | 11 | 18 |
| A.2 Networks | 11 | 18 |
| A.3 Databases | 11 | 18 |
| A.4 Machine learning | 5 | 18 |
| Theme B: Computational thinking and problem-solving | ||
| B.1 Computational thinking | 5 | 5 |
| B.2 Programming | 40 | 42 |
| B.3 Object-oriented programming (OOP) | 7 | 23 |
| B.4 Abstract data types (HL only) | 0 | 23 |
| Practical work and case study | ||
| Case study | 15 | 30 |
| Internal assessment: the computational solution | 35 | 35 |
| Collaborative sciences project | 10 | 10 |
| Total | 150 | 240 |
Source: IB Computer Science subject brief, first assessment 2027.
The table shows where the extra HL time goes. HL students spend much longer on machine learning (18 hours compared with 5), object-oriented programming (23 compared with 7) and the case study (30 compared with 15). They also study abstract data types, which SL students do not.
💡 Learn how each part of the IB grading system affects your final Diploma score.
Theme A: Concepts of Computer Science
Theme A is the theoretical foundation of the course. It explains how computing systems work, from the hardware inside a single computer to the networks and data that connect them. It is assessed in Paper 1.
- A.1 Computer fundamentals: how computer systems are built and how they work at a basic level.
- A.2 Networks: how devices communicate and share data, locally and across the world.
- A.3 Databases: how data is organised, stored and retrieved. Databases were an optional topic in the previous course and are now part of the core for every student.
- A.4 Machine learning: how computers learn from data. The IB describes the new course as "future-facing", and machine learning is a key part of this. HL students spend more than three times as long on this topic as SL students.
Theme B: Computational Thinking and Problem-Solving
Theme B is about using computing to solve problems. It is assessed in Paper 2, where you write answers in your chosen programming language.
B.1 Computational thinking is a structured process for solving problems. The IB defines it as the ability to:
- specify a problem in its computational context and set success criteria
- break complex real-world problems into smaller, manageable problems
- abstract and generalise problems so you can design algorithms
- test and evaluate solutions to improve them.
The other Theme B topics are:
- B.2 Programming: the largest topic in the course, at 40 hours (SL) and 42 hours (HL). You learn to write programs in Java or Python.
- B.3 Object-oriented programming (OOP): a way of designing programs around objects. SL students are introduced to OOP, while HL students study it in much greater depth.
- B.4 Abstract data types (HL only): more advanced ways of organising data in programs.
💡 Find out why you may want a qualified IB teacher as your tutor.
The Case Study
The course includes a case study, which the IB uses so that emerging technologies can be studied during the life of the course. In the previous course, only HL students studied the case study, and it was assessed in a separate Paper 3. In the new course:
- both SL and HL students study the case study
- it is assessed through three questions in Paper 1
- HL students spend 30 teaching hours on it, and SL students spend 15.
What Has Changed From the Previous Course?
The IB says the content has been revised so that the focus is computer science, not information technology. The main changes are:
- Option topics have been removed. The previous course had four options (databases, modelling and simulation, web science and object-oriented programming). Their key ideas have been absorbed into the core syllabus.
- Paper 3 has been removed. The case study is now assessed in Paper 1.
- The case study is now in the SL course too. Previously, it was for HL students only.
- Programming is assessed in a real language. The previous course assessed algorithms in pseudocode and had no set language. Now, every student answers programming questions on Paper 2 in Java or Python.
- Machine learning is a new core topic.
- The internal assessment has a new focus on the computational thinking process. Otherwise, the IB describes it as similar to the previous IA.
Skills You Will Develop
The IB says the course enables students to:
- develop conceptual understanding that connects different areas of computer science, and other DP subjects
- use computational thinking to design and implement solutions to local and global problems
- analyse and evaluate solutions in a range of contexts
- approach unfamiliar situations with creativity and resilience
- evaluate the impact of emerging technologies
- communicate and collaborate effectively
- understand the environmental, economic, cultural and social impact of computer science, and its ethical implications.
These skills are useful well beyond the course. They support university study in computer science, engineering, data science and many other fields.
Internal Assessment: The Computational Solution
The internal assessment (IA) is called the computational solution. It is compulsory for all students and is worth 30% of the final grade at SL and 20% at HL. The IB recommends 35 teaching hours for it at both levels.
You develop a computational solution to a real-world problem of your own choosing. The IB describes the IA as a "unifying assessment". It brings together Theme A and Theme B: you use the computational thinking process and show your skills in algorithmic thinking and programming.
A strong IA follows the computational thinking process from start to finish:
- Specify the problem: choose a real, specific problem and define clear success criteria.
- Decompose and abstract: break the problem into manageable parts and design your algorithms.
- Develop: build the solution using the concepts, skills and tools from the course.
- Test and evaluate: check your solution against your success criteria and explain how it could be improved.
Your teacher will share the official IA criteria from the subject guide, so make sure you know exactly how your work will be marked. Need help planning your IA? See our IB internal assessment support.
💡 Check out these five key habits of high-achieving IB students.
The Collaborative Sciences Project
All group 4 students complete the collaborative sciences project (10 hours). You work with students from other science subjects on a shared, interdisciplinary project, applying what you have learned to a real-world problem.
External Assessment Overview
The external assessment is two written papers, for both SL and HL. Together, they are worth 70% of the final grade at SL and 80% at HL.
| Component | What it covers | SL | HL |
|---|---|---|---|
| Paper 1 | Questions on the four Theme A topics three questions on the case study | 1h 15m (35%) | 2h (40%) |
| Paper 2 | Questions on Theme B topics, in Java or Python additional HL questions on OOP and abstract data types | 1h 15m (35%) | 2h (40%) |
| Internal assessment | The computational solution | 35 hours (30%) | 35 hours (20%) |
Source: IB Computer Science subject brief, first assessment 2027.
Programming is required for some Paper 2 questions. These questions come in two equivalent versions, one in Java and one in Python. You answer the version for the language you studied.
Assessment Objectives
The IB assesses the course against four assessment objectives (AOs):
| Objective | What you need to show |
|---|---|
| AO1 | Knowledge and understanding of computer science facts, concepts, principles and terminology, and of methods for solving problems with computational thinking |
| AO2 | Application of that knowledge and those methods, including presenting information appropriately |
| AO3 | Constructing, analysing and evaluating problem specifications, system requirements, success criteria, testing strategies and programs |
| AO4 | Applying computational thinking skills to solve real-world problems with computer science solutions |
Tips for Success in IB Computer Science
We asked our IB tutors for their advice on succeeding in the new course:
- Code regularly in your chosen language. Programming is the biggest topic in the course, and Paper 2 now asks you to write real Java or Python. Practise a little every week, not just before exams.
- Practise computational thinking explicitly. Use the four steps (specify, decompose, abstract, test and evaluate) on every problem. They underpin Paper 2 and your IA.
- Study the case study throughout the course. It is now worth three questions on Paper 1 for every student. Learn its technologies, terms and context well.
- Do not neglect Theme A. Networks, databases and machine learning are all core now, so there are no options to skip. Make clear notes for each topic.
- Start your IA early. Choose a real problem that interests you, and set measurable success criteria before you start coding.
- Test your code thoroughly. Check normal, boundary and unexpected inputs, and be able to explain your testing strategy.
- Think about impact and ethics. Be ready to discuss the social, environmental and ethical effects of technologies such as machine learning.
- Check practice materials against the new syllabus. Questions from the previous course can still help, but skip anything on Paper 3, the old options or pseudocode-only algorithms.
💡 Practice is key. Find out why past papers are the ultimate tool for IB exam preparation.
Common Mistakes to Avoid
- Treating the case study as an HL-only topic. It is now on Paper 1 for both SL and HL students.
- Choosing a vague IA problem. A broad or unclear problem leads to weak success criteria and a weak evaluation.
- Learning to read code but not write it. Paper 2 asks you to write working code in Java or Python.
- Skipping testing and documentation. These matter in both Paper 2 and the IA.
- Using old-course materials without checking. Paper 3, the options and pseudocode-only questions are no longer part of the course.
Frequently Asked Questions
When is the new IB Computer Science course first examined?
The new course was first taught in August 2025, and its first exams are in May 2027. Students sitting exams in November 2026 are on the previous course.
Should I choose Java or Python?
Both are accepted equally, and Paper 2 offers equivalent questions in each language. In practice, your school usually decides which language it teaches. You must answer in the language you studied.
Is Paper 3 still part of IB Computer Science?
No. Paper 3 has been removed. The case study is now assessed in Paper 1, at both SL and HL.
Can IB Computer Science be my group 4 science?
Yes. Computer Science is a group 4 science, so you can take it as your science subject.
What is the difference between SL and HL?
HL students study the same topics in more depth, plus abstract data types (HL only). HL exams are longer (4 hours compared with 2 hours 30 minutes), and the IA is worth 20% at HL compared with 30% at SL.
Do I need coding experience before starting?
No. The course builds programming skills from the start. Some experience is helpful, though, because programming is the largest topic in the course.
Get Support With IB Computer Science
The new course asks more of every student: real programming on Paper 2, a case study for everyone and machine learning in the core. Our experienced IB Computer Science tutors can help you master each topic, plan a strong IA and prepare for your exams, online wherever you are.
