Internal Assessment (IA) Overview

The Internal Assessment (IA) is the coursework component of IB Diploma Programme Computer Science. You identify a problem that interests you, design a computational solution for it, build the product, and document your work. The IA is worth 30% of your final mark at SL and 20% at HL, with the same criteria applied to both levels.

This page reflects the 2027 syllabus (first assessment May 2027). If you are sitting May 2026, your requirements are different – ask your teacher.

What you submit

The IA submission is made up of three files:

File	Format	Purpose
Documentation	Single PDF, 5 sections (one per criterion), max 2,000 words	The write-up that evidence-based mark scores are drawn from
Video	mp4 / avi / wmv, max 5 minutes	Demonstrates the product’s full functionality and examples from your testing
Appendices	Single PDF, full source code + any additional resources	Not used for awarding marks directly, but full source code is required to award full marks for Criterion D techniques

Four terms to get straight:

Solution = the documentation + the video (what you submit for assessment against the criteria).
Product = the completed software only.
Documentation = the single PDF that holds Criteria A–E.
Appendices = a separate single PDF holding the full source code and any supporting materials.

Word counts are measured excluding code excerpts, comments and diagrams. The overall word count must be stated on the first page of the documentation. This is a hard rule, not a convention.

The documentation, video narration and appendices must all be in the same language.

Time and scope

35 hours of class time is recommended for IA work.
Choose a problem you find personally interesting – it does not need to come from an external “client,” and the 2027 guide does not require named client consultation. Any topic in computer science that you can motivate is acceptable.
Aim for a problem that is complex enough to stretch you but narrow enough to finish properly. Whole-school timetabling or full library management systems almost always bite off more than 35 hours allows.

The five criteria

The IA is marked out of 30 using five criteria. Each page below walks through one criterion in detail.

Criterion	Name	Marks	Recommended words	What it assesses
A	Problem specification	4	300	The problem scenario, success criteria, and computational context
B	Planning	4	150	Decomposition of the problem + a chronology (e.g. Gantt, Agile)
C	System overview	6	150	A system model a third party could use to recreate the product, plus a testing strategy
D	Development	12	1,000	The built product: techniques used, justification, functionality (via video), testing
E	Evaluation	4	400	Evaluation against the success criteria + justified improvements

Criteria A, B, C and E are process-oriented – they assess how you carried out the task. Criterion D assesses the final product, with the video as the primary evidence of functionality.

Marks are whole numbers only (no half-marks) and awarded using the best-fit model: pick the level descriptor that most accurately describes your work, even if not every bullet is met.

How the criteria connect

The success criteria you define in Criterion A flow through the rest of the project:

A -> B Your plan’s chronology addresses the requirements of the success criteria.
A -> C Your system model and testing strategy are driven by the success criteria.
A -> D Your code techniques and video functionality demonstrate how the product meets the success criteria.
A -> E Your evaluation tells the reader, criterion by criterion, how far the product met each success criterion.

If the success criteria are vague or unmeasurable, every later section suffers. Spend the time on A.

Academic integrity

All documentation, code and the video must be your own work.
The teacher may give written or oral feedback on one draft, but cannot edit your work.
The same piece of work cannot be submitted for both the IA and the Extended Essay.
Ethical obligations: if your solution involves anyone else’s data or systems, get consent and store data securely. Data collected for the IA may only be used for the IA.
Acknowledge every external source – libraries, code adapted from tutorials or repositories, datasets, AI tool outputs. Failure to acknowledge a source can be investigated by the IB as a breach of academic-integrity regulations.

Using AI tools

The IB’s general academic-integrity rules apply: any AI use must be acknowledged like any other source. In practice for the IA:

AI may be used to explain concepts, suggest debugging approaches, clarify syntax, or review your code for issues – the same things you might use a textbook or a tutor for.
Code generated, adapted, or substantially edited by AI must be cited at the point of use, with a note in your appendices listing the AI tool, the prompt or task, and what you changed yourself.
AI must not be used to generate the substance of your documentation prose.
If in doubt, acknowledge.

Authentication and moderation

Your teacher marks your IA. Their mark is provisional.
The IB takes a moderation sample from your school. If your work is in the sample, the IB moderator can adjust your school’s marks (up or down) to align with the IB standard.
Before submission, your teacher must authenticate your work as your own. They can only do this if they have seen the work develop across the 35 hours – they cannot authenticate something they only saw the day before submission.
Authentication may be checked by discussion, by reviewing earlier drafts, by checking citations, or by running the work through plagiarism detection.