The current IB Computer Science HL course, first assessed in May 2027, combines Theme A—computer fundamentals, networks, databases, and machine learning—with Theme B—computational thinking, programming, and object-oriented programming. HL also studies abstract data types in greater depth. Paper 2 programming questions are available in Java and Python. The StudyIB topic catalogue below currently retains resources organised under the legacy course whose final assessment is in 2026; use those resources for transferable concepts while mapping revision to the new Theme A/B guide.

Concepts in computer science

Connect computer fundamentals, networks, databases, and machine learning to system behaviour, limitations, security, and ethical consequences.

Computational problem-solving

Specify success criteria, decompose and abstract a problem, construct an algorithm, implement it, and evaluate the result against the original need.

Programming and tracing

Practise reading, tracing, testing, and writing programs in Java or Python, including OOP and abstract data types.

Assessment at a glance

For the IB Computer Science HL course first assessed in May 2027, written external assessment and the computational solution make up the final grade. Programming questions on Paper 2 provide Java and Python versions. Confirm your examination session and course language with your school.

Component	Format	Weighting
Paper 1	2 hours; Theme A concepts of computer science and the case study	40%
Paper 2	2 hours; Theme B computational thinking, programming, OOP, and abstract data types; Java or Python	40%
Internal assessment	35 hours; computational solution to a chosen real-world problem	20%

Sources: official IB Computer Science subject brief (first assessment 2027) and official IB Computer Science curriculum update.

Revision plan

1.Confirm that your syllabus is the first-assessment-2027 course and map any legacy StudyIB resource to the matching Theme A or Theme B objective.
2.Alternate concept recall with tracing, algorithm construction, programming, testing, and evaluation rather than revising definitions alone.
3.Practise case-study questions by linking technical knowledge to the supplied context, stakeholders, limitations, and ethical implications.
4.Use timed Paper 1 and Paper 2 sets, recording whether each error came from knowledge, algorithm design, code tracing, syntax, testing, or explanation.

Exam strategy

Start by identifying the input, output, constraints, success criteria, and required level of abstraction. Trace state changes carefully, use precise terminology, and explain why a solution meets the problem rather than presenting code without evaluation. On case-study questions, apply technical knowledge to the stated context instead of giving a generic answer.

Practise IB Computer Science (CS) HL questions

Frequently asked questions

Which syllabus applies to IB Computer Science HL?

The current IB Computer Science course began teaching in August 2025 and is first assessed in May 2027. The previous course has its final assessment in 2026, so students should not treat the two syllabus structures as interchangeable.

What does the IB Computer Science HL course first assessed in 2027 cover?

HL covers Theme A—computer fundamentals, networks, databases, and machine learning—and Theme B—computational thinking, programming, object-oriented programming, and abstract data types. It also includes a case study, computational solution, and collaborative sciences project.

How is IB Computer Science HL assessed from 2027?

HL Paper 1 lasts two hours and contributes 40%; Paper 2 lasts two hours and contributes 40%; the computational solution internal assessment contributes 20%.

Which programming languages are used in the current IB Computer Science exams?

For programming questions on Paper 2, the course first assessed in 2027 provides equivalent Java and Python versions. Students answer using the language they studied.

Does the StudyIB Computer Science topic list use the new 2027 numbering?

The current StudyIB topic catalogue still includes resources organised under the legacy course whose final assessment is in 2026. Many underlying concepts remain useful, but 2027 candidates should map them to the new Theme A and Theme B syllabus and confirm coverage with the official guide and their school.

IB Computer Science (CS) HL

1 System Fundamentals

1.1 Systems in Organisations

1.2 System Design Basics

2 Computer Organisation

2.1 Basic Architecture

2.2 Advanced Memory

2.3 Application Software

2.4 Data Representation

2.5 Logic in Computing

4 Networks

4.1 Network Fundamentals

4.2 Data Transmission

4.3 Wireless Networking

4.4 General Principles

4.5 Connecting Computational Thinking and Program Design

4.6 Introduction to Programming

5 Abstract Data Structures (HL)

5.1 Recursive Thinking (HL)

5.2 Two-Dimensional Arrays (HL)

5.3 Stacks and Queues (HL)

5.4 Linked Lists (HL)

5.5 Trees (HL)

5.6 Applications of Data Structures (HL)

6 Resource Management (HL)

6.1 System Resources (HL)

6.2 Role of the Operating System (HL)

7 Control (HL)

7.1 Centralized Control Systems (HL)

7.2 Distributed Systems (HL)

How to study IB Computer Science (CS) HL