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Tested and works for all demo programs - please contact me if this breaks any of your working code!

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Error Checks

The site aims to enforce the statically-typed nature of pseudocode - i.e. assigning a STRING to an INTEGER variable should be forbidden. Some combinations are allowed, however - such as assigning a CHAR to a STRING or an INTEGER to a REAL. Other additional checks to ensure valid pseudocode are also in place

The site has been well-tested and there aren't any bugs we are aware of, however, if you believe the site is incorrectly giving you an error & preventing your code from running, you can disable the error-checking

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Turning this on will disable the warning message if using the LENGTH function to get the number of elements in an array

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IGCSE Syllabus (Pseudocode p35) O-Level Syllabus (Pseudocode p35) A-Level Syllabus A-Level Pseudocode Guide A-Level Pseudocode Functions Report Bugs
YouTube Tutorials Discord Help
AssemblyCode BooleanLogic CIESchedule Program52
DemosπŸ§‘πŸ»β€πŸ« Keyword ListπŸ“œ Monthly Challenge: Getting...πŸ“†
{"0":"Algorithms","1":"Selection","2":"Iteration","3":"Arrays","4":"Records","5":"ENUMs","6":"Custom Modules","7":"Files","8":"Object-Oriented Programming","9":"Abstract Data Types","10":"Sets","11":"Pointers","12":"Recursion","13":"Exam Questions","14":"Games","15":"Mathematics","16":"Art","17":"Utilities","18":"Other"}

Welcome to Pseudocode Pro

This site was developed to solve the problems of students either being completely stuck with pseudocode, or attempting a solution, but having no way of actually validating if it would work (other than a manual trace table). This site supports the entire Cambridge IGCSE (0478), O-Level (2210) and 9618 A-Level pseudocode specifications from the guide/syllabus, with extension modules supporting sound, canvas, events, custom html etc

Below are lists of both the currently support pseudocode and general website features:

  • πŸ“¦ Variables & Constants
  • βž• Arithmetic & Logical Operators
  • πŸ“₯πŸ“€ INPUT & OUTPUT
  • β“βŒ IF/ELSE & CASE
  • πŸ” FOR/WHILE/REPEAT...UNTIL Loops
  • πŸ”§ FUNCTIONS & PROCEDURES
  • πŸ”’ BYVAL & BYREF
  • πŸ”’ ARRAYs
  • πŸ“’ TYPEs (Records & Enums)
  • πŸ“„ File Handling (Text & RANDOM)
  • 🧩 Object-Oriented Programming
  • πŸͺ£ Sets
  • πŸ‘‰ Pointers
  • --- Extra Non-Syllabus Features ---
  • πŸ”Š Sound
  • 🎨 Canvas
  • πŸ–²οΈ Events
  • πŸ–₯️ Custom HTML

Additional programs uploaded by the community can be found on the search page.

While you are here, why not try one of the many - and ever increasing list of - pseudocode coding challenges.

To support hosting & domain costs, for $2, a premium account can be purchased - this has the following benefits:

Those last 2 features are currently in progress, so an extra 3 months free will be given to anyone who buys a license now to acknowledge this

For any issues, feature requests, comments etc, you can contact me

Token List

Work in progress: some buttons currently don't work...just select "All"

Token Description Example Parameters

Thanks for using the site - I hope you enjoy it and if you do, it would mean a lot if you could share it with your friends too :)

Drag & drop code or data files here

{"c":"\/\/ * Code Author: SharpPencil\n\/\/ * Date: 2026\/04\/07\n\/\/ * Description: The a part of a text based adventure game. (5 parts total)\n\/\/ * Categories: \n\n\/\/ Choices\r\nPROCEDURE FightPath()\r\n\tOUTPUT \"Fight. That is what King Crownelius taught you. You swing your blade at the field of butterflies.\"\r\n\r\n\tIF Strength >= 8 THEN\r\n\t\tOUTPUT \"You dash towards the butterflies, and blood splatters as you tear through one, their wings ripping like paper. One swings at you from behind. You flap your wings once, launching you into the sky. As you fall back down, you slice him in half. You make quick work of the rest of them, slicing through their flesh like butter. You look over the red covered arena, wiping blood off your blade. Serves them right.\"\r\n\t\tOUTPUT \"-+5 Skill Points!-\"\r\n\t\tStatPoints \u2190 StatPoints + 5\r\n\t\tOUTPUT \"Spend your skill points! Total:\"\r\n\t\tCALL SkillShop()\r\n\r\n\tELSE \r\n\t\tOUTPUT \"You dash towards the butterflies, and blood splatters as you cut one. They swing at you, which you narrowly avoid, before thrusting your sword, finishing them. A butterfly attacks you from behind, managing to land a shallow cut on you. You slowly defeat the enslaught of butterflies, being hit occassionally. Overall, you lost:\"\r\n\t\tHP \u2190 HP - (30 - Defence)\r\n\t\tOUTPUT HP\r\n\t\tOUTPUT \"HP\"\r\n\tENDIF\r\n\tOUTPUT \"Without hesitation, you head to the castle. There, you meet more resistance. A chill goes through your feathers as you sense a looming presence. A large butterfly, flapping its wings slowly descends to your level dual wielding a sword and a mace. It somehow adjusts the crown on its head, before approaching you slowly.\"\r\n\r\n\tREPEAT\r\n\t\tCALL ButterflyBossfight()\r\n\tUNTIL HP <= 0 OR BHP <= 0\r\n\r\n\tIF BHP <= 0 THEN\r\n\t\tOUTPUT \"You take a deep breath. The king has been slain. Your people have been avenged. You sit quietly in the bloodfilled castle. Was this worth it? More blood had been spilled. Maybe innocent blood, unaware of what happened. Is this what your people would have wanted? You sit there, pondering the question. (WIN)\"\r\n\tELSE \r\n\t\tOUTPUT \"GAME OVER.\"\r\n\tENDIF\r\n\tCALL GameEnd()\r\nENDPROCEDURE\r\n\r\nPROCEDURE CharismaStrength()\r\n\r\n\tIF Strength = 5 THEN\r\n\t\tOUTPUT \"You barely manage to take them on. Covered in blood, some your own and some of theirs, you take a look at your injuries. They hit you for:\"\r\n\t\tHP \u2190 HP - (30 - Defence)\r\n\t\tOUTPUT HP\r\n\t\tOUTPUT \"HP\"\r\n\t\tOUTPUT \"You sense a looming presence. A large butterfly, flapping its wings slowly descends to your level dual wielding a sword and a mace. It somehow adjusts the crown on its head, before approaching you slowly.\"\r\n\r\n\t\tREPEAT\r\n\t\t\tCALL ButterflyBossfight()\r\n\t\tUNTIL HP <= 0 OR BHP <= 0\r\n\r\n\t\tIF BHP <= 0 THEN\r\n\t\t\tOUTPUT \"You take a deep breath. The king has been slain. Your people have been avenged. You sit quietly in the bloodfilled castle. Was this worth it? More blood had been spilled. Maybe innocent blood, unaware of what happened. Is this what your people would have wanted? You sit there, pondering the question. (WIN)\"\r\n\t\tELSE \r\n\t\t\tOUTPUT \"GAME OVER.\"\r\n\t\tENDIF\r\n\t\tCALL GameEnd()\r\n\tELSE \r\n\t\tOUTPUT \"They swing back, blocking your sword. The others attack you simaltaniously, the fight a blur, you end up on the floor. Your vision blurs slowly, before going fully black.\r\n GAME OVER.\"\r\n\t\tCALL GameEnd()\r\n\tENDIF\r\nENDPROCEDURE\r\n\r\nPROCEDURE CharismaPath()\r\n\tOUTPUT \"You start trembling, your blade shaking in your beak. You take a deep breath. Maybe you could try a different approach.\"\r\n\r\n\tIF Charisma >= 10 THEN\r\n\t\tOUTPUT \"You stop trembling, and clear your throat. You explain to the guards that you're a butterfly, just from a different kingdom. They don't look convinced, so you begin flapping your wings in a very butterfly like way, and talk about how your time in a larvae was. Now thoroughly convinced, they smile at you, and ask what happened. You tell that you must urgently speak to their king. They nod, and ask you to follow them. You're taken with them to the castle. The guards let you in, and then you explain that you need immediate audience with the king, alone.\"\r\n\r\n\t\tIF Charisma < 15 THEN\r\n\t\t\tOUTPUT \"They narrow their eyes, suspicious of you. One of them grabs your wings, and shakes it slightly. Knowing your about to be outed, you swing at them.\"\r\n\t\t\tCALL CharismaStrength()\r\n\t\tELSE \r\n\t\t\tOUTPUT \"They nod, as they then exit the room immediately. The king emerges, a curious expression on his face. Now's your chance. You instantly draw your sword.\"\r\n\t\tENDIF\r\n\r\n\t\tREPEAT\r\n\t\t\tCALL ButterflyBossfight()\r\n\t\tUNTIL HP <= 0 OR BHP <= 0\r\n\r\n\t\tIF BHP <= 0 THEN\r\n\t\t\tOUTPUT \"You take a deep breath. The king has been slain. Your people have been avenged. You sit quietly in the bloodfilled castle. Was this worth it? More blood had been spilled. Maybe innocent blood, unaware of what happened. Is this what your people would have wanted? You sit there, pondering the question. (WIN)\"\r\n\t\tELSE \r\n\t\t\tOUTPUT \"GAME OVER.\"\r\n\t\tENDIF\r\n\t\tCALL GameEnd()\r\n\tELSE \r\n\t\tOUTPUT \"You tremble harder, and fail to clear your through. Your voice shaking, you explain to the guards that you're a butterfly, just from another kingdom. They don't look convinced, so you begin flapping your wings. This seems to have the opposite effect. Your chest tightening, you begin talking about your love for honey- butterflies love that, right? Outraged by confusing them for bee's they attack simaltaniously. The fight a blur, you end up on the floor. Your vision blurs slowly, before going fully black.\r\n GAME OVER\"\r\n\t\tCALL GameEnd()\r\n\tENDIF\r\nENDPROCEDURE\r\n\r\nPROCEDURE FrontGate()\r\n\tOUTPUT \"You head to the front gate. Be direct. That is what your father Wing-ston Churchil taught you.\"\r\n\r\n\tIF Strength >= 5 THEN\r\n\t\tOUTPUT \"You take a deep breath, gripping your blade tighter with your beak, and burst through the gates. Shrapnel polluting the air, the butterflies scream and scatter in every direction. Ironic for them to be afraid. Armed butterflies surround you, somehow holding weapons.\"\r\n\tELSE \r\n\t\tOUTPUT \"You take a deep breath, and strike the gates hard with your blade. It barely dents the large gate. You strike again, to no avail. The gates open slowly, revealing a group of armed butterflies. They surround you, somehow holding weapons.\"\r\n\tENDIF\r\n\tOUTPUT \"A chill goes down your feathers. You didn't anticipate this many guards. What do you do?\r\n 1. Fight.\r\n 2. Charisma\"\r\n\tCALL Decision()\r\n\r\n\tIF Choice = 1 THEN\r\n\t\tCALL FightPath()\r\n\tELSE \r\n\t\tIF Choice = 2 THEN\r\n\t\t\tCALL CharismaPath()\r\n\t\tENDIF\r\n\tENDIF\r\nENDPROCEDURE","t":"The Bird Knight (3)"}
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