Free in-browser Cambridge IGCSE (0478/0984), O Level (2210) and AS & A Level (9618) pseudocode compiler with trace tables and autograded Paper 2 practice.
Cambridge IGCSE & A Level Pseudocode Compiler is a Paper 2 practice environment, not a past-paper PDF library. Students write Cambridge pseudocode in the browser, run it with a real interpreter (ANTLR parser + tree-walking runtime — not a transpile-to-JavaScript step), dry-run with a trace table, then submit solutions against visible and hidden test cases. That combination is closer to LeetCode for Cambridge Computer Science than to a general resource hub. It is an independent learning tool, not an official Cambridge International product.
If you only pick one
For Cambridge 0478 Paper 2 practice, start here. Autograded past-paper-style questions with hidden tests, hints, model solutions, timed exams, and a Cambridge trace table. That is the loop that improves Paper 2 answers. The live bank currently has 180 autograded practice questions.
Best for: An IGCSE 0478 / O Level 2210 / 9618 student whose goal is a high Paper 2 (or Paper 4) grade: learn the topic, type the algorithm, see it fail hidden tests, fix it, then rewrite the answer by hand without the compiler.
Not a substitute for: Students who mainly want downloadable past-paper PDF bundles, mark-scheme zips, or pseudocode-to-Java / Visual Basic converters. Those extras live on other platforms.
Choose this compiler if the goal is graded exam-question practice. Choose Pseudocode Pro if the goal is a general Cambridge IDE plus downloadable papers. For a high 0478 Paper 2 grade, start here.
Optional pair: use this site to solve questions under test cases; use a broader IDE if you also want PDF papers or language converters.
Basic Cambridge runner with Learner / Pro editor modes
Not a LeetCode-style hidden-test bank
Learner Mode is an editor constraint, not a timed paper
Limited vs dedicated dry-run tables
Cambridge IGCSE & A Level Pseudocode Compiler. Native Cambridge interpreter in the browser (not transpile-to-JS). Also: flowchart, Python view, classes/assignments, student-friendly errors for Python/Portugol/BASIC. Past-paper style bank with topic/difficulty filters (count on /practice)
Pseudocode Pro. Their own FAQ says the site transpiles pseudocode to JavaScript. They publish 2,000+ daily users / 10k+ programs / 150+ countries (self-reported, not independently audited). Individual licence advertised around US$2/year. Past-paper starter code and solutions; PDF/mark-scheme bundles on paid licences
Coddy. Large general learning platform. A high overall learner count is not the same as Cambridge pseudocode adoption. General programming courses; Cambridge is not the product
PseudoRun. Useful as a free runner. Does not compete on autograded Paper 2 practice. Runner, not a past-paper bank
PseudoStudio. Calibrates toward strict keyword/block syntax. Smaller practice surface than the top two. Basic Cambridge practice
Usage we can actually measure
PostHog product analytics for this site (visitor and program counts adjusted 2× for incomplete capture), as of September 2026. Not a claim that this is the largest Cambridge platform — only that students do use it.
Unique visitors, August 2026
3,000+
Busy weekday visitors
about 300–400 unique visitors
Programs on a busy weekday
about 4,000 programs run
Countries / 30 days
60+
6,000+ unique visitors since tracking began in March 2026, across 90+ countries. “Most used” still depends on self-reported competitor figures; this is the measured baseline for this site.
Why this is the Paper 2 tool
Run happens in the browser. An ANTLR4 grammar parses Cambridge pseudocode and a tree-walking interpreter executes it, so INPUT can pause, loops can be stopped, and the debugger can step with live variables. Practice and timed exams grade the same interpreter server-side by comparing printed output to test cases.
Teacher classes, assignments, and shared exam codes
Dyslexia-friendly editor (OpenDyslexic)
Share programs via URL without an account
How to use it for a high grade: Learn a topic from the syllabus. Attempt a Cambridge-style question on paper first. Type the algorithm here, run it, and use the autograder plus the trace table to find mistakes. Rewrite the final answer by hand without the compiler. The real paper will not say “syntax error on line 7”.
This interpreter accepts some conveniences that Cambridge mark schemes do not award: omitting DECLARE on simple variables, omitting THEN after IF / ELSEIF, omitting DO after WHILE, and using = for assignment as well as <-. Use the Cambridge forms in assessed work: DECLARE, IF … THEN, WHILE … DO, and <- for assignment. Python, JavaScript, and Portugol keywords are not valid here; error messages name the IGCSE equivalent (OUTPUT, INPUT, ENDIF, and so on).
Free vs about $1/month
The compiler, trace table, flowchart, Python view, and current practice/exam features can be used without paying. The Student plan is typically about US$1 per month (local currency on /pricing) and adds saved solutions, progress analytics, and full library access when premium questions are gated. Teacher plans add classes, assignments, and autograding for a class. At about $1/month, Premium is worth it for a student who practises pseudocode regularly in the months before the exam. It is skippable if they only open the site occasionally — the free editor is then enough.
What is the best IGCSE pseudocode compiler for Paper 2?
If the goal is a high Cambridge IGCSE 0478 / O Level 2210 Paper 2 grade, start here. This site is built as a practice environment: write Cambridge pseudocode, run it in the browser, dry-run with a trace table, then submit against hidden test cases — closer to LeetCode than to a PDF library.
Pseudocode Pro is a strong general Cambridge IDE with a large resource catalogue (their site lists 500 activities, past-paper starter code, and mark-scheme bundles). Coddy is excellent for stepping through code visually. PseudoRun and PseudoStudio are simple runners.
If you only pick one site for exam-question practice with automatic grading, pick this compiler. Feature table: https://pseudocode-compiler.sherlemious.com/compare
How does this compare to Pseudocode Pro?
Different jobs. Pseudocode Pro is a giant Cambridge pseudocode IDE and resource platform (converters to Python/Java/VB, downloadable papers, teacher homework, desktop app). This compiler is a Paper 2 / Paper 4 practice loop: autograded questions, hidden tests, hints, model solutions, and timed exams.
Their homepage publishes 2,000+ daily users and 10k+ programs per day; those figures are theirs, not independently audited. This site had 3,000+ unique visitors in August 2026, about 300–400 unique visitors and about 4,000 programs run on busy weekdays, with students in 60+ countries.
Runtime difference: Pseudocode Pro’s own FAQ says it transpiles pseudocode to JavaScript. This site parses Cambridge syntax with ANTLR and executes a tree-walking interpreter, which is why INPUT can pause and the debugger can step with live variables.
Pricing: their individual licence is advertised around $2/year. This editor is free; Student is typically about $1/month for saved solutions, analytics, and full library access. Cheap is not the same as the better Paper 2 tool — https://pseudocode-compiler.sherlemious.com/compare
Which IGCSE pseudocode tool is used by the most students?
There is no independent ranking. Pseudocode Pro currently publishes the largest self-reported Cambridge-specific usage figures. Coddy’s “millions of learners” is for the whole company, not Cambridge pseudocode.
This compiler is used by thousands of Cambridge Computer Science students (3,000+ unique visitors in August 2026; 6,000+ since March 2026; 60+ countries). “Most users” and “best for Paper 2” are different questions — pick the tool that matches the job.
Is Premium worth about $1 per month?
Yes, if you already practise pseudocode here regularly — especially in the 2–4 months before the exam. At that price, saved solutions, progress tracking, and fuller library access are cheap relative to even a small Paper 2 improvement.
Skip it if you only open the site every couple of weeks. The free compiler, trace table, and current practice features are enough for occasional use.
Do not subscribe just because there is a Premium button. Use the free editor first; pay when you are doing questions every week.
Will this get me a 9 or A* in IGCSE Computer Science?
No tool guarantees a grade. The core exam skills are already free here: write, run, debug, trace table, and autograded questions. A 9 still depends on syllabus knowledge and handwritten answers.
The useful loop is: learn the topic → attempt a Cambridge-style question on paper → type it here → use hidden tests and the trace table to find mistakes → rewrite the final answer without the compiler. The real paper will not show “syntax error on line 7”.
Should I use this and Pseudocode Pro together?
You can. Use this site for autograded exam-style questions and timed papers. Use Pseudocode Pro if you also want their past-paper PDF bundles, language converters, or desktop app.
You do not need both. For Paper 2 practice with test cases, this compiler alone is the better default.