How IB assessment works when you are planning a retake

IB assessment has three separate steps: marks for each component, a final subject grade from 1 to 7, and the Diploma award conditions. A higher IA mark affects the weighted subject total; it does not directly add a Diploma point. For a retake, establish which assessments must be completed again before booking a host.

How component marks become a score: a 60% worked example

Use the guide for your exact subject, level and examination session. For Math AA SL in the 2026 and 2027 sessions, the official subject brief, first assessment 2021, gives paper 1 and paper 2 a 40% weighting each and the exploration 20%. The IB mathematics page identifies this as the course assessed until November 2028; the new curriculum is first assessed in 2029. The example below uses the SL weights, not the different HL paper weights.

That 60 is not automatically a grade 6: the appropriate session’s boundaries determine the subject grade. This simplified example assumes final component marks and does not reproduce the IB’s complete assessment processing. If the final exploration mark were 18/20 instead of 16/20 with the same paper marks, the total would be 62/100; a subject-grade increase would still require crossing the relevant boundary. Convert differently weighted raw marks before adding them.

Use the boundary tool to explore a historical session, then the diploma-score guide to check the separate award conditions. For the core, the TOK–EE matrix shows how A–E grades translate into up to three points.

To interpret results, distinguish the candidate populations and editions in the May statistical bulletin analysis, then test individual grade changes against the worked core-points matrix.

Compare six worked IB retake score scenarios · Check eight subjects before retaking after a syllabus change

External assessment: exams and coursework

External assessment includes written examinations and some coursework marked by IB examiners. The IB assessment overview names the TOK essay and Extended Essay as examples of externally assessed coursework. A task completed at school is therefore not automatically an Internal Assessment.

Exam papers may test essays, structured questions, data analysis or multiple choice. Their number, format and weight depend on the exact subject, level and curriculum. Check which components your result includes before using a weighted-mark calculator.

Internal Assessment (IA)

Internal Assessment is initially marked by the teacher against IB criteria. The IB checks a sample to establish whether the school has applied those criteria consistently; marks may remain unchanged, rise or fall. The 2026 examiner instructions explain that an examiner’s mark on sampled work does not simply replace that student’s mark: a moderation factor may be applied to the school’s marks. Examples depend on the subject:

• Group 1 (Language A): the individual oral is an internal assessment component. Other components depend on the exact course and level; consult the current subject guide.
• Group 2 (Language B): Individual Oral
• Group 3 (Individuals & Societies): Research based essays or investigations
• Group 4 (Sciences): Scientific investigation (lab report)
• Group 5 (Mathematics): Mathematical exploration
• Group 6 (Arts): Portfolios, exhibitions and performances have different assessment routes across courses. Check which component is internally marked and which is externally assessed; do not treat every arts submission as IA.

The Core Components

Diploma candidates must also complete three core components:

• Theory of Knowledge (TOK): The exhibition is teacher-marked and externally moderated; the essay is externally marked, as set out in the TOK examiner instructions. The final TOK grade combines with the EE grade in the core-points matrix.
• Extended Essay (EE): An independent research paper of up to 4,000 words. Marked externally by IB examiners.
• Creativity, Activity, Service (CAS): CAS receives no grade or Diploma points. Completion is assessed by the school and is required for the Diploma. If it is incomplete, agree the remaining evidence and arrangements with the coordinator; registering for an exam does not complete CAS.

You Choose What to Retake

You can retake a subject without retaking the entire Diploma, but you must resit all written examinations in that subject. Existing non-examination component marks may carry forward if curriculum and assessment conditions allow; the coordinator must confirm this. Use the retake rules to check the registration scope before choosing papers.

The IB assessment principles, printed page 121, distinguish written examinations from other components. “Non-examination” can include written coursework. If new internally assessed work is required, ask the registering school about the teaching, supervision and authentication arrangements before assuming it can accept that work. Ask for the school’s coursework submission and authentication dates separately from its exam-registration deadline.

IBretake Is Exam Hosting Only

IBretake helps students find schools that can host selected retake exams. It does not arrange new IA, coursework, tutoring, oral preparation, or coursework supervision. If an existing IA mark or coursework component matters for your retake, confirm that separately with your previous school or the accepting IB coordinator.

Grade Boundaries Vary

Grade boundaries can change between sessions to maintain comparable standards. The IB describes a process using the quality of student work against grade descriptors, examiner judgment and statistical evidence in its explanation of grade boundaries. A historical percentage is useful context, not a guaranteed threshold for your next examination.

The 45 Point Scale

The Diploma total is up to 42 points from six subject grades plus up to 3 TOK/EE points. HL and SL grades count equally in that total. Reaching 24 is necessary but does not by itself award the Diploma: core completion, minimum HL/SL totals and the limits on low grades must also be satisfied. Check those conditions in the diploma-score guide linked above.