How Singapore Education Works | IB Diploma Assessment: Grades 1–7, Internal Assessment and Final Exams

Quick answer: The IB Diploma Programme assesses students through a mix of external examinations and internal or externally assessed coursework. Each subject receives a grade from 1 to 7, with 7 the highest. The final Diploma result combines six subject grades, with up to three additional points available from the Theory of Knowledge and Extended Essay matrix. CAS is compulsory but does not add points. Assessment is criterion-related: performance is judged against published standards, not simply by ranking students against one another.

This is different from assuming every task is a class test or that a student’s school percentage converts directly into an IB grade. The IB and the school use subject-specific assessment objectives and criteria. Students should understand each component and the evidence it requires.

At a glance

Each DP subject receives a grade from 1 (lowest) to 7 (highest).
External examinations form the basis for most subject assessments.
Internal assessment is marked by teachers and moderated by the IB in many subjects.
TOK and EE can contribute up to three combined bonus points.
CAS is compulsory but is not scored as points.

Criterion-related assessment, not a class ranking

The IB says Diploma results are determined by performance against set standards rather than each student’s position in an overall rank order. That means a student should focus on what assessment criteria require: analysis, accurate knowledge, evaluation, problem-solving, communication or practical technique depending on the subject.

A class average may help a teacher understand the cohort, but it does not define an IB grade by itself. Being top three in the class does not guarantee a 7; being below the median does not automatically mean a 4. Official subject criteria and grade boundaries for the relevant session matter. Read the IB assessment overview.

What grades 1 to 7 mean

Each DP course receives a grade from 1 to 7, with 7 the highest. The grade represents achievement against the subject’s assessment objectives and descriptors. Students should read the subject-specific criteria rather than interpret a 6 as a simple percentage band that works identically in every subject.

Different courses use different combinations of written examination, coursework, oral, practical or project components. A school report may use internal scales or predicted grades that are not the final result awarded by the IB. Ask the teacher which component the report reflects and what the feedback indicates.

External assessment: why final examinations matter

For most DP courses, written examinations at the end of the Diploma Programme form the basis of assessment. They are marked externally under IB procedures. Depending on the subject, papers may test knowledge, problem-solving, analysis, interpretation, argument, practical understanding or written communication.

Students should practise the actual course’s assessment style rather than assume all subjects are memory-based. A History response, Mathematics problem and Biology data-based question require different ways of demonstrating achievement. External assessment promotes consistency, but does not remove the need to understand course content throughout the two years.

Internal assessment: teacher feedback and moderation

Many IB subjects include school-based internal assessment tasks. Teachers mark work against relevant criteria, and the IB can moderate samples to help ensure standards are applied consistently. Other coursework components may be externally assessed. The balance depends on the course.

Internal assessment is not “free marks”. Students must follow task instructions, deadlines, research or practical requirements and authenticity rules. A polished report may still be weak if method, evidence or analysis fails to meet criteria. Ask how the component is assessed, how drafts and feedback are handled and what final submission rules say.

A Science internal assessment example

A student investigating an environmental question must use an appropriate method, record actual evidence, analyse results and discuss limitations. A graph alone does not demonstrate strong analysis; the student must explain what the pattern means and whether the method supports the conclusion.

If measurements vary, report them honestly. Do not remove inconvenient data or ask AI to invent a cleaner set. If the sample is small or a variable was not controlled, identify the limitation and explain its effect. Follow the school’s ethics and safety rules, especially where a project involves people or equipment.

TOK and Extended Essay: separate core assessments

TOK is assessed through an exhibition and an essay. The Extended Essay is an independent research paper of up to 4,000 words. These are not two more subjects graded on the same syllabus content. They assess reflection on knowledge and independent research.

TOK rewards clear arguments, examples and examination of assumptions. The EE requires a focused question, reliable evidence, a suitable method and a coherent line of reasoning. Both require students to follow current IB and school rules for authenticity and submission. Read TOK guidance and EE guidance.

How TOK and EE contribute up to three points

TOK and EE grades are combined using the IB matrix, with a maximum of three additional points toward the Diploma total. Not every combination earns bonus points; some combinations produce zero. CAS is different: it is compulsory and must be completed, but does not contribute numerical points.

Use the current IB matrix and Diploma passing criteria. Do not invent a conversion from a TOK exhibition mark or EE draft percentage into final bonus points. The school coordinator can explain the current matrix and assessment cycle.

Predicted grades versus final grades

Schools may provide predicted grades for university applications before final IB results are issued. These are estimates based on student performance and school judgement; they are not final IB grades. Universities may use predicted grades for conditional offers under their own procedures.

Ask what evidence the school uses for predictions, when they are finalised and whether an internal review process exists. The student’s performance can change after the prediction, and the IB awards the final result through official assessment. Do not assume a predicted 6 entitles a student to a final 6.

Grade boundaries and why percentages mislead

IB grade boundaries are subject- and session-specific and reflect the assessment design and standards. A raw percentage from one paper or school test does not automatically convert to a final 1–7 grade. Different components can be weighted differently, and the final grade reflects the subject’s overall requirements.

Students should use feedback to identify the next improvement: more precise explanation, stronger evaluation, fewer calculation errors, better practical analysis or more coherent argument. Chasing a guessed percentage boundary can distract from the quality of the work.

What if a student is unhappy with a result?

First review subject feedback and speak with the school’s IB coordinator about official post-results services available for the relevant session. Options and deadlines are governed by IB procedures and may include a re-mark or other review. A review is not a guarantee of an increase and may have a fee or other implications.

The school can explain the current process and advise which service is relevant. Do not rely on social media claims about automatic remark improvements. Follow the coordinator’s instructions and official deadlines.

How to prepare across the two years

Use the subject guide and assessment criteria from the start. After each task, identify one criterion to improve and use a new task to test whether learning transfers. For examinations, practise time management and unfamiliar question types. For internal assessment, maintain source logs, raw data, drafts and milestone records according to school rules.

Schedule the EE, TOK, CAS and six subjects together. A pupil who waits until the final term to organise the core may find deadlines collide with examinations and university applications. See the IP study-planning guide.

The conclusion: understand the evidence behind every grade

The IB Diploma is not a single examination paper or one percentage average. It combines six subject grades and the required core, using external examinations and internal or externally assessed coursework. Subject criteria, the TOK/EE matrix and Diploma passing conditions determine the outcome.

Students make better progress when they know which evidence is assessed and why. Instead of asking only “What grade did I get?”, ask “What did this task measure, what standard did I demonstrate and what can I improve in the next unfamiliar task?”

Frequently asked questions

What is the highest IB subject grade?

7 is the highest and 1 the lowest.

Are all IB assessments final examinations?

No. Many courses use internal assessment or coursework as well as external exams.

Are internal assessments marked only by the IB?

Teachers mark many internal components, with IB moderation; other coursework can be externally assessed.

Does every class percentage convert directly to an IB grade?

No. Grade calculation and boundaries are subject- and session-specific.

How many bonus points can TOK and EE contribute?

Up to three combined points under the IB matrix.

Does CAS add points?

No. CAS is compulsory but is not points-scored.

Are predicted grades final?

No. They are school estimates; the IB issues final grades.

Can a remark guarantee a higher result?

No. Post-results services follow official rules and do not guarantee an increase.

Official sources and update note

Reviewed 7 November 2026 against linked official guidance. This independent guide is not a school, university or admissions decision. Subject availability, entry criteria and examination requirements can change; verify the relevant year’s official pages and the student’s school handbook.