GCSE Computer Science specification
GCSE Computer Science teaches the principles of computation alongside practical programming: how computers represent and process data, how hardware, networks and systems work, and how to design, write, test and refine programs to solve problems. It builds computational thinking (decomposition, abstraction, algorithms, logic) and the technical foundations for A-level Computer Science and digital careers.
Assessed entirely by external examination across all boards - two papers, each worth 50%. One paper covers theory/computer-systems content; the other focuses on computational thinking, algorithms and programming. Practical programming is assessed within the written/on-screen exams rather than by coursework: the standalone Non-Examined Assessment (NEA / programming project) was removed (Ofqual/DfE, from 2019) because it could not be reliably authenticated, so any required practical programming time is now non-assessed classroom preparation. Some boards (Edexcel, Eduqas) deliver one paper as an on-screen programming exam in Python; others (AQA, OCR) test programming on paper using either a high-level language or the board's reference notation.
High-level topics
The main areas of content and what a student is expected to know and do.
The CPU and von Neumann architecture, the fetch-execute cycle, registers, clock speed/cores/cache and how they affect performance, plus embedded systems.
Primary storage (RAM, ROM, virtual memory), secondary storage types (magnetic, optical, solid state) and their characteristics, and how data and instructions are held.
Binary and hexadecimal, binary arithmetic and shifts, units of storage, and how characters, images, sound and instructions are represented in binary, including compression.
LANs/WANs, network topologies, wired vs wireless, protocols and the TCP/IP and OSI layered models, and factors affecting network performance.
Threats such as malware, phishing, social engineering, SQL injection and brute-force attacks, and the methods used to prevent and detect them (firewalls, encryption, authentication, anti-malware, penetration testing).
The role and functions of operating systems (memory/process/peripheral/user management) and utility software, and the relationship between hardware and software.
Decomposition, abstraction and algorithmic thinking; writing, tracing and correcting algorithms; standard searching (linear, binary) and sorting (bubble, merge, insertion) algorithms and their behaviour.
The three basic constructs (sequence, selection, iteration), variables and constants, data types, operators, subroutines/functions and parameters, and good programming practice.
Arrays/lists, records and 2-D structures; reading from and writing to files; and (on most specs) using relational databases and structured queries (SQL) to store and retrieve data.
Designing, writing, testing and refining working programs to a brief; validation and authentication, defensive design, error handling, and selecting/justifying test data - assessed in the exam, not by coursework.
Logic gates (AND, OR, NOT and combinations), truth tables and simple logic circuits/expressions relevant to how computers make decisions.
The difference between high-level and low-level (machine/assembly) code, the purpose of compilers, interpreters and assemblers, and common features of integrated development environments (IDEs).
The impact of digital technology on individuals, society and the environment; privacy, data protection, intellectual property and relevant legislation; and cultural and ethical issues.
Exam boards
The awarding bodies that offer this qualification, how their papers are structured, and what's distinctive about each - with links to the official specification.
AQA GCSE Computer Science
Papers & assessment
Untiered, linear; 2 papers, each 50%. Paper 1 'Computational thinking and programming skills' tests programming and computational thinking and is sat in a chosen language - candidates enter a language-specific variant (8525/1A C#, 8525/1B Python, 8525/1C VB.NET); Paper 2 'Computing concepts' (1h45, 90 marks) is a written theory paper. No NEA - programming is exam-assessed. Note: the spec was redeveloped (still code 8525) for first teaching Sept 2025 / first exams summer 2027 after DfE content changes - some content trimmed and relational databases/SQL emphasised.
What's distinctive
Offers a genuine choice of three exam programming languages (C#, Python, VB.NET) via separate paper variants. Defines its own pseudocode in the spec for use in questions where a specific language isn't required. From the 2027 series it increases focus on relational databases and SQL.
Specification
Past papers & mark schemes
Pearson Edexcel GCSE (9–1) Computer Science
Papers & assessment
Untiered, linear; 2 papers, each 50%. Paper 1 'Principles of Computer Science' (1CP2/01) is a written theory paper covering Topics 1–5. Paper 2 'Application of Computational Thinking' (1CP2/02) is an on-screen programming exam (2 hours, 75 marks) where candidates complete programming tasks on a computer in Python 3. No NEA/coursework.
What's distinctive
Paper 2 is a fully on-screen, hands-on programming exam in Python 3 (candidates amend supplied code files on a computer). Python 3 is the single examined language, defined via a published Programming Language Subset (PLS) document.
Specification
Past papers & mark schemes
OCR GCSE (9–1) Computer Science
Papers & assessment
Untiered, linear; 2 written papers, each 1h30, 80 marks, 50%. J277/01 'Computer systems' (theory) and J277/02 'Computational thinking, algorithms and programming', whose Section B assesses design/write/test/refine programming skills on paper. No NEA - a programming task must still be undertaken during the course but is non-assessed practical preparation.
What's distinctive
Programming is answered on paper using either the candidate's chosen high-level language or OCR's own Exam Reference Language (a defined pseudocode-style notation), rather than via on-screen coding.
Specification
Past papers & mark schemes
WJEC Eduqas GCSE Computer Science
Papers & assessment
Untiered, linear; 2 components, each 50%, no NEA. Component 1 'Understanding Computer Science' is a written exam (1h45) covering theory. Component 2 'Computer Programming' is an on-screen exam (2 hours) requiring access to Python 3; candidates produce a programmed solution to a set task that forms the basis of the assessment.
What's distinctive
Eduqas is the version of WJEC's GCSE offered to schools in England. On-screen programming component is sat in Python 3. First awarded summer 2022.
Specification
Past papers & mark schemes
WJEC GCSE Computer Science (Wales)
Papers & assessment
Untiered, linear; assessed by Component 1 and Component 2, no NEA. This is WJEC's Qualifications Wales-approved GCSE for centres in Wales (distinct from the Eduqas version used in England). A redeveloped WJEC spec is for first teaching from September 2025, with first award in summer 2027.
What's distinctive
Wales-only counterpart to Eduqas; structurally similar (theory paper plus a programming component). From Sept 2025 a new Made-for-Wales specification applies (first award 2027). Spec code not confirmed from a primary source, so omitted.
Past papers & mark schemes
All five boards offer an untiered, linear GCSE with two exam components each worth 50% and no coursework/NEA - the standalone programming project was removed years ago because it couldn't be reliably authenticated, so practical programming is now assessed inside the exams and any required project time is non-assessed preparation. The big practical difference is HOW programming is examined. Edexcel (Python 3) and Eduqas/WJEC (Python 3) sit one component fully ON-SCREEN, with candidates coding live on a computer. AQA and OCR assess programming on PAPER: OCR lets students answer in their own high-level language or OCR's Exam Reference Language, while AQA defines its own pseudocode and - uniquely - lets centres choose between three examined languages (C#, Python, VB.NET) through language-specific paper variants. Edexcel, Eduqas and WJEC effectively standardise on Python. Paper timings vary a little (OCR 2×1h30; AQA Paper 2 1h45; Edexcel/Eduqas on-screen paper 2h). On currency: OCR (J277), Edexcel (1CP2) and Eduqas (C500QS) continue on their 2020 specifications, while AQA's 8525 has been redeveloped (same code) and WJEC's Wales spec replaced, both for first teaching September 2025 and first exams summer 2027 following minor DfE content changes (e.g. trimming dated networking/protocol detail and reinforcing relational databases/SQL). Students sitting exams in 2026 are on the existing versions; those starting courses from September 2025 are on the updated AQA/WJEC content.
Original sources
Straight from the awarding bodies - the specifications these summaries are drawn from.
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