IB Computer Science New Syllabus 2027 Explained

The new IB Computer Science course, first examined in May 2027, replaces the old core and options with two themes: concepts of computer science and computational thinking. Students now write real code in Java or Python, the separate HL Paper 3 has gone, and the case study moves into Paper 1 for both SL and HL. The internal assessment is a computational solution worth 30% at SL and 20% at HL.

Key takeaways

First teaching was August 2025 and the first exams are in May 2027.
Every student studies Theme A (concepts) and Theme B (computational thinking and programming).
Paper 2 is sat in either Java or Python, chosen by the school.
Paper 3 no longer exists; the pre-seen case study is examined in Paper 1.

Who does the new syllabus apply to?

It applies to students who started the Diploma Programme in August or September 2025 and later. The IB's own computer science updates page states that the new course launched in February 2025 for first teaching in August 2025, with first assessment in May 2027. Students who sat exams in 2026 were the last cohort on the old syllabus.

If you use past papers, be careful: papers from 2026 and earlier follow the old structure. They are still useful for topics such as data structures and networks, but not for exam format.

What do you study in the new course?

AssessPrep's summary of the ten main changes explains that the course is built around two themes, and every student studies both. The old optional topics, such as databases, web science and object-oriented programming, no longer exist as separate options.

Theme	Content	Examined in
A: Concepts of computer science	Computer fundamentals, networks, databases, machine learning	Paper 1
B: Computational thinking and problem-solving	Programming, algorithms, object-oriented programming, abstract data types at HL	Paper 2
Case study	A pre-released topic on an emerging technology	Paper 1

Machine learning is the most visible new topic. The IB also notes that the course includes a case study on emerging technologies, and the subject now sits with the sciences in Group 4.

Do you have to use Java or Python?

Yes. The IB states that students can study the course using either Java or Python. AssessPrep adds that there are two separate versions of Paper 2, one for each language, and that schools choose at department level. You cannot answer in a different language.

This is a real change for students. Under the old course, exam answers were written in IB pseudocode, so it was possible to do well with limited practical coding. Now you need to read, trace and write actual code by hand. From my own IB teaching, the students who cope best are those who code a little every week from the start of Year 1, not those who cram programming before mocks.

How is the new course assessed?

RevisionDojo's assessment overview sets out the model: SL and HL students complete two written papers and a computational solution. Paper 1 assesses Theme A and the pre-seen case study, and Paper 2 assesses Theme B, including programming in Java or Python.

Component	What it tests	Weight
Paper 1	Theme A concepts, plus case study questions	Part of the external 70% (SL) or 80% (HL)
Paper 2	Theme B programming and algorithms in Java or Python	Part of the external 70% (SL) or 80% (HL)
Internal assessment	A computational solution you design and build	30% at SL, 20% at HL

HL students answer more questions and study extra content, including abstract data types. Ask your teacher for the exact paper lengths and mark totals from the subject guide, since your school has the official document.

What happened to the case study and Paper 3?

Under the old syllabus, only HL students sat Paper 3, which was based on a pre-seen case study. That paper has been removed. RevisionDojo's case study guide confirms that the case study is now assessed in Paper 1, Section B, for both SL and HL students.

ManageBac's guide to the new course adds a useful detail: SL students explore two challenges from the case study and HL students explore four. The case study changes each year, so make sure your notes match your own exam session.

What is the new internal assessment?

The IA is called the computational solution. You identify a real problem, plan and build a program that solves it, and document your work. ManageBac notes that the IA has a new structure with extra class hours allocated to it.

Choose a problem that is small enough to finish and has real logic in it. A booking system for a club, a revision tracker or a simple inventory tool works better than an ambitious game you cannot complete. Your documentation and testing earn marks, not just the code.

How should you prepare?

Code weekly. Short, regular practice in your school's language beats long sessions before exams.
Trace code by hand. Paper 2 is written on paper, so practise following loops and method calls with a trace table.
Learn Theme A actively. Use flashcards and self-quizzing for definitions in networks, databases and machine learning.
Start the case study early. Research each term in the booklet and write your own explanations.
Plan the IA backwards from the deadline, with time for testing.

Free courses help with the programming side: see free Python courses with certificates and how to learn Python fast. To see how your subject grades add up to a diploma score, use our IB points calculator, and for UK applications read UCAS tariff points explained.

Frequently asked questions

Is pseudocode still used in IB Computer Science?

Programming questions in the new Paper 2 are answered in Java or Python, not IB pseudocode. Check your school's subject guide for the exact conventions used in your papers.

Is there still a Paper 3 in IB Computer Science HL?

No. From May 2027, Paper 3 has been removed. The pre-seen case study is examined in Paper 1 for both SL and HL.

How much is the IA worth in IB Computer Science?

The computational solution is worth 30% of the final grade at Standard Level and 20% at Higher Level.

IB Computer Science New Syllabus: What Changes for First Exams in May 2027