Tools

ZAK's interactive tools, built for the Cambridge syllabus.

Not generic — every tool here maps to something you'll be asked to do in the exam.

AI-narrated video overview of this pageYouTube

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Or browse all 36 tools below.

Programming & algorithms

Write it, run it, trace it — Paper 2 and Paper 4 skills in the browser.

Real interpreter

Pseudocode Playground

Write CAIE pseudocode, press run, see the output. Errors point to the exact line.

Open

Paper 2 & 4

Python Playground

Real Python 3 in your browser — input(), files, classes, exceptions — with a trace table and the Python twin of every pseudocode example.

Open

Paper 4

Java Playground

The real Java compiler in your browser — Scanner, files, classes, exceptions with the JDK's own messages — with a trace table and the Java twin of every Python example.

Open

Paper 4

VB.NET Playground

Visual Basic .NET console programs compiled by Microsoft's own compiler in your browser — Console.ReadLine, files, Structures, classes — with a trace table.

Open

Databases

SQL Lab

Query a ready-made school database: SELECT, JOIN, GROUP BY, INSERT, CREATE TABLE — with real keys and referential integrity.

Open

AS & A2

Assembler & CPU Simulator

A real two-pass assembler that checks every mnemonic, operand and label, then steps through an animated fetch–decode–execute cycle with the exam trace table.

Open

A2 §20.1

Declarative Lab (Prolog)

Facts, rules and queries with every answer, the resolution trace and the errors an A2 examiner would flag.

Open

Paper 2

Flowchart Studio

Draw flowcharts with the Cambridge symbols and run them; turn pseudocode into a flowchart and back; check your drawing against the answer. Structure charts and state diagrams too.

Open

Paper 2 & 4

Pseudocode Translator

One program, four languages: CAIE pseudocode into Python, VB.NET or Java — the three languages the papers accept — with every difference explained.

Open

Step by step

Python Paths

Learn Python one numbered step at a time — O Level / IGCSE or 9618 Paper 4 — each step checked against hidden tests, with progress per block and Continue where you left off.

Open

AS & A2

Data Structures Playground

Stacks, linear and circular queues, linked lists with a free list, binary trees and hash tables — arrays plus pointers, one operation at a time, with the pseudocode for each.

Open

All levels

Algorithm Lab

Bubble and insertion sort pass by pass, linear and binary search with the low/high/mid table, a recursion call-stack tracer, Dijkstra and A* on your own graph, and a perceptron that learns.

Open

A2 §20.1

OOP Designer

Class diagram ⇄ code: describe classes, inheritance and containment and get the diagram plus skeleton code in pseudocode, Python, VB.NET or Java — or read the diagram from pseudocode.

Open

Paper 2

Trace Table Generator

Paste any algorithm and get the complete trace table — the exact skill Paper 2 tests.

Open

Theory labs

Paper 1 and Paper 3 topics you can actually operate: numbers, gates, networks, the CPU, the OS, the compiler.

Paper 1 · 3

Number Systems Lab

Binary ↔ denary ↔ hex ↔ two's complement, binary arithmetic, shifts and masks with the working, plus A2 floating point (mantissa + exponent, normalisation, ZAK's method) with every step of the working shown. Practice mode included.

Open

Paper 1 · 3

Data Lab

File-size calculations with the working, run-length and dictionary compression you can watch, lossy sliders, character codes, pixels and samples, and A2 file organisation.

Open

Paper 1 · 3

Networks Lab

Parity blocks and checksums, packet switching over routers, IP and subnet arithmetic, the URL-to-page journey, TCP/IP layers, RSA and the TLS handshake, and a blockchain you can break.

Open

Databases

Database Designer

Normalise to 3NF with every partial and transitive dependency checked, draw ER diagrams and resolve many-to-many, design a 2210 table with validation — then create it in the SQL Lab.

Open

A2 §16.2

Compiler Lab

Infix ⇄ Reverse Polish with the stack drawn at every step, RPN evaluation, BNF grammars tested with derivations and syntax diagrams, lexical analysis with a symbol table, parse trees and the four stages of compilation.

Open

Paper 1 · 3

Systems Lab

Fetch–decode–execute in register-transfer notation with the buses lit, interrupts on a timeline, control systems that run your pseudocode, OS scheduling and paging, pipelining.

Open

Paper 1 & 2

Logic Gates Lab

Type an expression and get the circuit and truth table — or draw the circuit with gates and read off its expression.

Open

A2 §15.2

Boolean Algebra & K-map Lab

Karnaugh maps with the optimal loops, sum-of-products, simplest form and every Boolean algebra law named — plus live adders and flip-flops, and past-paper practice marked like the mark scheme.

Open

Exam practice

Real questions, assignments, quizzes and full mock papers — marked.

Auto-marked

Programming Tasks

Exam-style scenario tasks marked automatically against normal, boundary and abnormal test data — pseudocode or Python, hidden tests, model answers.

Open

Paper 2

Testing & Validation Lab

Normal / boundary / abnormal / extreme test data for any spec, validation rules on real inputs, check digits with the working, syntax vs logic vs run-time errors.

Open

With solutions

ZAK Assignments

A full assignment for every topic, built by AskZ from ZAK's own class assignments — figures, model answers, mark scheme, self-marking and a PDF download. Three sets per topic.

Open

Mark schemes + examiner comments

Topical Past Paper Questions

Every real Cambridge question since 2015 (plus the still-relevant ones back to 2010), filed by topic with its mark scheme and what the examiner said about it. Answer, reveal, self-mark — or let AskZ mark it like an examiner.

Open

Teachers

Paper Builder

For teachers: build a class test, monthly test, mid-term or full mock. Set the marks, the time and each topic’s share, then fill it with real Cambridge questions or AskZ-written ones. Download it as a PDF, or share one link so the class sits the same paper. Free access for school emails.

Open

Never before

Statometer

Every topic measured against every real Cambridge paper: how often it is set, the odds it appears in your next paper, marks a paper, trend, command words and what inside it gets asked — ranked, and re-ordered by your own quiz record.

Open

Exam intelligence

Syllabus Map

Every topic × every year since 2015, coloured by how much of the paper it took, with command words and when it was last set — click through to the questions.

Open

Practice

Topic Quizzes

Auto-marked MCQs with an explanation for every answer. Earn XP.

Open

New · game

Examiner's Traps

Real mistakes from Cambridge examiner reports, each named with its paper. True or false in 15 seconds, streaks, a shareable score — missed traps come back in your Today card.

Open

Study & organise

Notes, videos, flashcards and your exam timetable.

All 30 topics

AskZ Smart Notes

Complete notes for every topic, written by AskZ from ZAK's material and the mark schemes — infographics, quiz, past papers inside; download as slides.

Open

500+ videos

Video Lectures

Every lecture, past-paper walkthrough and Zakathon revision session on ZAK's YouTube channel, indexed by syllabus topic — watch here, or from the topic page's Resources card.

Open

Memorise

Flashcards

1,600+ shuffled cards across every topic of 2210 / 0478 and 9618. Flip, rate, drill your weak ones.

Open

Organise

Exam Timetable & Planner

Paper dates, sessions and Key Times for your Cambridge zone, a live countdown, calendar export and a week-by-week revision plan.

Open

Plan ahead

University Planner

Tick your A Levels and see which Computer Science degrees stay open in Pakistan and abroad, why, and the university's own rule — plus an IBCC calculator, what-if, compare, a parents' PDF and every admission deadline.

Open

NewCS Games · 16 to play

Want to play instead? CS Games

Quiz battles, a daily CS word, SQL whodunnits, logic-gate puzzles and arcade — every game drills the syllabus. Solo against AskZ bots, with friends, or with your whole class. Free, no sign-up.

Play now

ArenaZ RoyaleZ CodleZ TraceZ GolfZ GateZ DetectiveZ + all 16 →