The IB exam structure is subject-specific. Paper 1, Paper 2 and Paper 3 do not have universal meanings across the Diploma Programme, while SL and HL students may face different content, durations and numbers of papers. Exams are administered in May and November sessions, with schools assigned to official exam zones so papers can be delivered securely at appropriate local times.
This guide explains the current structure using Biology, Chemistry, Physics, Economics and Mathematics: Analysis and Approaches as examples. Always check the subject guide for your examination year because assessment models change when a syllabus is revised.
How IB exams fit into subject assessment
Written examinations form the largest part of the final assessment in most IB Diploma Programme subjects. They are externally assessed, meaning completed scripts are marked through the IB's external assessment process rather than graded solely by your classroom teacher.
Most subjects also include an internal assessment, such as a scientific investigation, mathematical exploration or Economics commentary portfolio. Internal assessment is marked by the teacher and moderated by the IB, so your final subject grade normally combines examination performance with coursework.
The IB uses criterion-related assessment. Your performance is judged against defined standards, not against your rank within your class. Raw marks from each component are combined according to their official weightings before grade boundaries are applied.
What Paper 1, Paper 2 and Paper 3 mean
A paper number identifies an examination component within a particular subject. It does not identify one question type across the whole IB.
For example:
- In the current sciences, Paper 1A contains multiple-choice questions and Paper 1B assesses data analysis and experimental skills.
- In Economics, Paper 1 is an extended-response examination.
- In Mathematics: Analysis and Approaches, Paper 1 is completed without a calculator.
- In Mathematics AA HL and Economics HL, Paper 3 adds an HL-specific assessment.
- In the current Biology, Chemistry and Physics courses, there is no Paper 3.
This is why revising simply for “Paper 1 technique” is too vague. You must know the command terms, resources, timing and response format for your specific subject and syllabus version.
Current paper structures by subject
The following comparison covers the current courses examined in 2026. Durations and weightings come from official IB subject briefs and guides.
| Subject and level | External papers | Total external time | Main formats |
|---|---|---|---|
| Biology, Chemistry or Physics SL | 2 | 3 hours | Paper 1A multiple choice, Paper 1B data or experimental questions, Paper 2 short and extended responses |
| Biology, Chemistry or Physics HL | 2 | 4 hours 30 minutes | Same broad paper structure as SL, with greater depth, breadth and demand |
| Economics SL | 2 | 3 hours | Paper 1 extended response; Paper 2 data response |
| Economics HL | 3 | 4 hours 45 minutes | Paper 1 extended response; Paper 2 data response; Paper 3 policy paper |
| Mathematics AA SL | 2 | 3 hours | Paper 1 without technology; Paper 2 with technology |
| Mathematics AA HL | 3 | 5 hours | Papers 1 and 2 plus a technology-enabled problem-solving Paper 3 |
Biology, Chemistry and Physics
For first assessment in 2025, the revised Biology, Chemistry and Physics courses replaced the older three-paper science model. SL and HL students now take Paper 1 and Paper 2, with Paper 1 divided into parts 1A and 1B.
In all three subjects, Paper 1 lasts 1 hour 30 minutes at SL and 2 hours at HL. Paper 2 lasts 1 hour 30 minutes at SL and 2 hours 30 minutes at HL. Together, the papers contribute 80% of the subject grade, while the scientific investigation contributes 20%.
Paper 1A tests rapid selection and application through multiple-choice questions. Paper 1B emphasizes data, graphs, uncertainty and experimental reasoning, while Paper 2 uses short-answer and extended-response questions. Students using older past papers must therefore recognize that the former science Paper 3 and option-topic structure no longer matches the current course.
Targeted practice is available in the Biology Questionbank, Chemistry Questionbank and Physics resources.
Economics
Economics illustrates how paper numbers can represent entirely different skills. At SL, Paper 1 assesses extended economic argument and evaluation, while Paper 2 requires students to interpret data and apply theory to supplied material.
HL students also complete Paper 3, a policy paper requiring quantitative work, economic analysis and a justified policy recommendation. It is not simply a more difficult version of Paper 2. It assesses the additional breadth and quantitative demands of HL through a distinct task.
Students should therefore practise diagrams, calculations, real-world application and evaluative writing rather than treating every paper as an essay test. The IB Economics Questionbank can be filtered for focused paper-style practice.
Mathematics: Analysis and Approaches
Mathematics AA SL students take two papers. Paper 1 prohibits calculator use, while Paper 2 requires or permits the specified technology, normally an approved graphic display calculator under the applicable examination instructions.
HL students take longer versions of Papers 1 and 2 and complete Paper 3, consisting of two compulsory extended problem-solving questions. Paper 3 rewards sustained reasoning, the connection of multiple mathematical ideas and clear working rather than isolated routine calculations.
A correct final answer does not always earn full credit without supporting method. Practising complete solutions through the Mathematics AA Questionbank helps develop the communication needed for method and reasoning marks.
SL and HL differences
The official distinction is broader than “HL has an extra paper.” The IB recommends 150 teaching hours for SL and 240 hours for HL, and HL courses contain greater breadth, depth or both.
Depending on the subject, HL may involve:
- additional syllabus content;
- more demanding applications and synthesis;
- longer examinations;
- different component weightings;
- an additional Paper 3.
Economics HL and Mathematics AA HL have Paper 3 examinations, but current Biology, Chemistry and Physics HL do not. In those sciences, HL demand is expressed through additional content, greater conceptual depth and longer versions of Papers 1 and 2. The number of papers alone is therefore not a reliable measure of difficulty.
IB timezones and official exam zones
Students often say “IB timezones,” but current official timetables use exam zones A, B and C. A school is assigned a zone and follows the local morning and afternoon start times published for that zone.
Exam zones exist because the IB operates internationally. Coordinated timings, supervision requirements and, where necessary, additional paper variants reduce the opportunity for questions to circulate between candidates who have not yet taken an examination. Variants must assess the same syllabus and be held to common assessment standards, but students should not assume that every candidate worldwide necessarily receives an identical question booklet.
Your zone is determined through your school, not by your nationality or the timezone on your phone. The official timetable states that a school's allocated zone does not change between sessions and that published local start times do not need a separate daylight-saving adjustment. Confirm your exact reporting time with your coordinator rather than converting it independently.
RevisionDojo's guides to IB exam zones, exam start times and reading an IB timetable can help you turn the official schedule into a personal calendar.
May and November examination sessions
The IB publishes separate May and November examination schedules. These are full assessment sessions, not different qualification levels, and the same subject standards apply in both.
Your school registers you for the appropriate session. Subject availability and school arrangements can differ, so candidates should not assume that every course or retake will automatically be available at their preferred school in both sessions.
Each timetable is divided into morning and afternoon sessions. These labels are administrative examination periods, not separate versions of the Diploma Programme. An examination cannot be moved to a different date or time merely for convenience; changes require authorization under IB assessment procedures.
When planning revision, copy every paper separately into your calendar. Include the date, session, level, duration, permitted equipment, arrival time and room specified by your school.
Common mistakes when preparing for IB papers
- Using obsolete papers without checking the syllabus: Pre-2025 science papers include structures and option topics that no longer match current exams.
- Assuming every HL subject has Paper 3: This is true for some courses, not all.
- Revising content without practising format: Multiple choice, data response, policy recommendations and extended mathematics require different methods.
- Using the wrong calculator rules: Mathematics AA Paper 1 and Paper 2 have different technology conditions.
- Guessing an exam time from an online post: Only the school coordinator can confirm your assigned schedule and reporting instructions.
- Ignoring the instructions page: Choice rules, required resources and answer-booklet directions can affect how marks are earned.
A practical paper-by-paper preparation method
Create a one-page profile for every paper showing its duration, weighting, question types, equipment and timing targets. Then complete timed questions in the same format instead of mixing unrelated skills in every study session.
After each attempt, classify lost marks as knowledge, interpretation, method, communication or time management errors. Use Jojo AI to clarify specific mistakes, then answer a similar question without notes. RevisionDojo's subject Questionbanks and predicted papers with model answers and video solutions support per-question review before you progress to complete timed papers.
Conclusion
IB exam structure becomes manageable once you separate four ideas: the subject-specific meaning of each paper, the distinction between SL and HL, the administrative role of exam zones, and the difference between May and November sessions. Paper numbers are not universal, HL does not always mean Paper 3, and exam zones affect secure administration rather than the syllabus standard.
Confirm your requirements using the current subject guide and your coordinator's timetable. Then use RevisionDojo Questionbanks, Jojo AI feedback and per-question video solutions to practise the exact format you will face rather than relying on general revision alone.
Sources and referenced URLs
- IB assessment and examinations overview
- Official IB examination schedules
- May 2026 examination schedule
- IB Biology subject brief
- IB Chemistry subject brief
- IB Physics subject brief
- IB Economics HL subject brief
- IB Mathematics AA subject brief
- RevisionDojo Biology Questionbank
- RevisionDojo Chemistry Questionbank
- RevisionDojo Physics resources
- RevisionDojo Economics Questionbank
- RevisionDojo Mathematics AA Questionbank
- RevisionDojo exam-zone guide
- RevisionDojo exam start-time guide
- RevisionDojo guide to reading the examination schedule
- RevisionDojo predicted papers and video solutions