The complete IB Extended Essay guide

The Extended Essay is a 4,000-word independent research essay. From the May 2027 session it is marked out of 30 (Framework for the essay 6, Knowledge and understanding 6, Analysis and line of argument 6, Discussion and evaluation 8, Reflection 4); through November 2026 it is marked out of 34 on the older criteria. Together with TOK it contributes up to 3 bonus points to your Diploma.

The Extended Essay (EE) is one of the three core requirements of the IB Diploma Programme, alongside Theory of Knowledge and CAS. It is a 4,000-word independent research paper that asks students to investigate a topic of personal interest within one of the IB subject areas. For many students, the EE represents their first experience with sustained academic research, and it contributes up to 3 bonus points towards the IB Diploma when combined with the TOK grade.

This guide covers everything you need to know about the Extended Essay: from choosing a research question to understanding how examiners apply the assessment criteria. Whether you are choosing a research question or revising a final draft, the information below will help you understand what examiners are looking for and how to maximise your score.

What is the IB Extended Essay?

The Extended Essay is a required component for all IB Diploma candidates. It is an in-depth study of a focused topic, usually in one of the student's DP subjects. Through November 2026 it can also be an interdisciplinary World Studies essay; from May 2027 that option is replaced by the interdisciplinary extended essay. The essay must be the result of the student's own research and must demonstrate the ability to formulate an appropriate research question, engage in personal exploration of the topic, communicate ideas effectively, and develop a reasoned argument.

The EE is supervised by a teacher at the student's school, but the research and writing must be the student's own work. The IBO allocates approximately 40 hours of work to the Extended Essay, spread across the final two years of the Diploma Programme. Students meet their supervisor, including three formal reflection sessions, and the supervisor gives guidance on method, structure and academic conventions but does not edit or rewrite the essay.

Word count and timeline

The maximum word count for the Extended Essay is 4,000 words. This limit includes the introduction, body, conclusion, quotations, and any footnotes or endnotes that are not references. It does not include the contents page, headers, maps, charts, diagrams, annotated illustrations, tables, equations, formulas and calculations, citations and references, the bibliography, or the reflection form. There is no abstract: it was dropped in 2018.

There is no minimum word count, but an essay far below the limit often lacks the depth the upper levels describe. Going over the limit means the examiner stops reading at 4,000 words and does not assess anything beyond that point. Most strong essays use most of the limit without padding.

A typical timeline for the Extended Essay spans 12-18 months:

Months 1-3: Subject selection, initial research, supervisor assignment, research question formulation
Months 4-7: Deep research, data collection, experimentation (for sciences), primary source analysis (for humanities)
Months 8-10: First draft writing, supervisor feedback sessions
Months 11-12: Revision, final draft, formatting, and submission

Schools set their own internal deadlines, which come well before the IB's final submission deadline. Your school's EE policy says what happens if you miss one, so check it early.

Choosing a research question

The research question (RQ) is arguably the most important element of the Extended Essay. A well-crafted RQ provides focus, determines the scope of research, and guides the entire argument. A poor RQ leads to unfocused essays that struggle to demonstrate analysis.

Characteristics of a strong research question:

Specific and focused: "To what extent did propaganda influence voter turnout in the 1933 German federal election?" is better than "How did propaganda affect Germany?"
Answerable within 4,000 words: If the question requires a book-length answer, it is too broad
Researchable: Sufficient primary and secondary sources must be available
Analytical, not descriptive: Questions beginning with "To what extent," "How far," or "Evaluate" tend to produce better arguments than "What" or "Describe" questions
Connected to a subject area: The RQ must fit the methodology of your chosen subject, or of both subjects in an interdisciplinary essay

Common mistakes in research question formulation include choosing a topic that is too broad (resulting in superficial treatment), too narrow (running out of material before 4,000 words), too personal (lacking academic rigour), or too reliant on a single source.

Structure and formatting

The Extended Essay guide says these structural elements must be present in every essay: a title page, a contents page, an introduction, the body, a conclusion, and a reference list or bibliography. Within the body, follow the conventions of your subject. For May 2027 onward the guide also sets the format: font size 12, 1.5 line spacing, page numbers on every page after the contents page (mandatory), and no student, supervisor or school name anywhere in the file. The framework below fills in those elements:

Title page: from May 2027, your student code, your research question, the DP subject the essay relates to (for an interdisciplinary essay, the two DP subjects and the interdisciplinary framework it connects with) and the word count; through November 2026, the title, the research question, the subject the essay is registered in (with the category for a language essay, or the theme and the two subjects for a world studies essay) and the word count. From May 2027, if any footnote does more than give a reference, include it in the word count on the title page and add the statement "the stated word count includes explanatory footnotes". Leave off your name, your supervisor's name, your candidate session number and your school's name or number: Extended Essays are marked anonymously.
Table of contents: With page numbers
Introduction (300-400 words): Context, research question, scope, methodology overview
Body (3,000-3,200 words): Organised into logical sections with clear headings, presenting evidence, analysis, and argumentation
Conclusion (200-300 words): Direct answer to the RQ, summary of findings, acknowledgement of limitations, suggestions for further research
Bibliography: one consistent citation style, such as MLA, APA, Chicago or Harvard, used throughout
Appendices (if needed): Raw data, interview transcripts, supplementary materials

For science subjects, the structure typically mirrors a lab report: introduction, methodology, results, analysis, conclusion. For humanities and social sciences, a thematic or chronological structure with argumentative sections works best.

Assessment criteria (A-E)

From the May 2027 session every Extended Essay is marked out of 30 on these five criteria, the same in every subject:

Criterion	Focus	Max Marks
A: Framework for the essay	Research question, research methods, structure	6
B: Knowledge and understanding	Knowledge of the topic, subject terminology and concepts	6
C: Analysis and line of argument	Analysis of the research, a coherent argument	6
D: Discussion and evaluation	Significance of the findings, evaluation of the essay	8
E: Reflection	Reflective statement in the RPF, up to 500 words	4

Through November 2026 the essay is marked out of 34 on the older criteria instead: Focus and method (6), Knowledge and understanding (6), Critical thinking (12), Presentation (4) and Engagement (6, marked on the three RPPF reflections). See what changed in 2027.

Criterion D (Discussion and evaluation) carries the most weight at 8 marks. It rewards a balanced discussion of what your findings mean, supported by evidence, and an evaluation of the essay itself, with its strengths and limitations. Criterion C, analysis and line of argument, is where descriptive essays that report information without analysing it lose marks first.

Criterion E (Reflection) is marked on the reflective statement in the RPF, up to 500 words, written after the final reflection session, the viva voce. It rewards evaluative reflection, with specific examples, on how the EE affected you as a learner, showing growth and transfer of learning; a description of the process is the lowest level. Through November 2026 the equivalent criterion is Engagement, marked on the three RPPF reflections, 500 words in total.

Common mistakes

Issues that commonly cost Extended Essays marks:

Descriptive rather than analytical writing: Reporting what happened or what sources say without evaluating, comparing, or arguing
Research question too broad: Attempting to cover too much ground, resulting in superficial treatment
Over-reliance on secondary sources: particularly in subjects such as History, where primary sources strengthen the argument (a Psychology EE, by contrast, is built on published research)
Poor source evaluation: Citing sources without assessing their reliability, bias, or limitations
Weak conclusion: Failing to directly answer the research question or introducing new material in the conclusion
Inconsistent referencing: Mixing citation styles or failing to cite all borrowed ideas
A reflection that only describes: treating the RPF (or, through November 2026, the RPPF) as a diary of the process instead of evaluating what the research taught you
Exceeding word count: Including material that will not be read or assessed

How to score an A

In recent sessions an A on the Extended Essay has been 27 to 34 marks out of 34, under the criteria in force through November 2026. For May 2027 onward the essay is marked out of 30 against rewritten criteria, and the IB sets those grade boundaries only after the session is marked, so no A threshold exists for the new scale yet. Either way, an A needs strong work across the criteria. A-grade Extended Essays tend to share these characteristics:

Clear, focused research question that is interesting and allows for in-depth analysis within 4,000 words. The best RQs often emerge from genuine curiosity rather than from trying to find a "safe" topic.

Analysis, discussion and evaluation demonstrated through evaluation of evidence, consideration of counter-arguments, acknowledgement of limitations, and nuanced conclusions. A-grade essays rarely present black-and-white answers; they acknowledge complexity.

Effective use of subject-specific methodology: In sciences, this means rigorous experimental design and statistical analysis. In humanities, it means engagement with historiographical debates or literary theory. In social sciences, it means appropriate research methods and ethical considerations.

Evaluative reflection in the reflection form: what the research changed in the student as a learner, with specific examples. Criterion E is marked on that form, so that is where it has to be visible.

Careful structure and referencing: clear structure, consistent formatting, accurate referencing and polished academic writing. From May 2027 structure counts under Criterion A, the framework for the essay (through November 2026 it is Presentation, 4 marks), and a clear structure also makes the argument easier to follow.

Final checklist before submission

Before submitting your Extended Essay, verify the following:

Word count is no more than 4,000 (check what is included and excluded)
Your name, your supervisor's name, your candidate session number and your school's name or number appear nowhere in the essay
Research question is clearly stated on the title page and in the introduction
Every section of the body directly relates to answering the research question
Conclusion directly answers the research question with evidence from the body
All sources are cited consistently using one citation style throughout
Bibliography is complete and properly formatted
November 2026 and earlier: the RPPF contains three reflections in total, the last of which is the viva voce reflection, within a 500-word limit
May 2027 onward: the RPPF is replaced by the RPF, a single reflective statement of up to 500 words written after the viva voce, and Criterion E is marked on that statement rather than on the essay
Table of contents has accurate page numbers
Headers and formatting are consistent throughout
No material in appendices that should be in the main body
You have proofread the essay yourself for grammar, spelling and clarity (the guide says you must do your own proofreading)

If you want criterion-based feedback on your Extended Essay before submission, ask your supervisor first, because an AI check is outside help on the EE. If they agree, IBLens can mark your Extended Essay against the EE criteria for your session, the 34-mark set or the new 30-mark set, in a minute or two.

For more on how IB assessment criteria work across all essay types, see our guide on IB essay criteria explained. If you are working on an IA instead, check our Internal Assessment guide.