A calm truth about the IB grading scale
In the IB, results rarely feel like “just a number.” They feel like a story you’ve been living for two years: late-night problem sets, a stubborn paragraph that finally clicks, a lab that worked only after the third trial. Then May (or November) arrives and you’re told your effort becomes a 1 to 7.
That’s why the IB grading scale can confuse students and parents at first. It isn’t built to mirror percentages or rank you against classmates. It’s built to measure how well you met specific standards. Once you understand that philosophy, the rest of the system becomes much easier to navigate, and much easier to plan around.
IB grading scale overview (quick checklist)
Use this as your fast mental model of IB results:
-
Each IB subject gets a final grade from 1 to 7.
-
You take six subjects (a mix of SL and HL).
-
Your six subject grades add up to a maximum of 42 points.
-
TOK and the Extended Essay (EE) can add up to 3 bonus points.
-
CAS is required but not graded.
-
Maximum possible IB Diploma score: 45 points.
-
Final grades depend on your total marks compared to IB grade boundaries, which vary by subject and session.
If you want to see how grade boundaries shift over time, use the IB Grade Boundaries page and compare recent sessions.
How IB exams are assessed: external vs internal
A big reason the IB feels different is that most subjects blend two types of assessment.
External assessment (final exam components)
External assessments are the parts most families picture when they imagine the IB: timed papers, structured questions, essays, and sometimes externally assessed recordings or written tasks depending on the subject. These are marked by trained examiners, which helps keep the system globally consistent.
External assessment often carries the majority weighting in a subject. That matters because it means exam-day performance can move your final IB grade more than students expect.
Internal assessment (IA)
Internal assessments are marked by your teacher and then moderated by the IB. Think investigations, lab reports, portfolios, presentations, or orals. The moderation piece is important: it’s how the IB tries to keep standards aligned across schools worldwide.
If you want your IA to feel less like guesswork, tools that mirror the rubric help. RevisionDojo’s IB Coursework Grader can give rubric-aware feedback loops, and the IB Coursework Examples: IA, EE and TOK Exemplars library helps you see what strong work looks like.
The 1 to 7 IB grading scale (what the numbers mean)
Every IB subject ends with a grade from 1 (lowest) to 7 (highest). While exact descriptors vary by subject, the broad meaning stays consistent:
-
7: Excellent performance
-
6: Very good performance
-
5: Good performance
-
4: Satisfactory performance (often considered “passing”)
-
3: Mediocre performance
-
2: Poor performance
-
1: Very poor performance
Two practical takeaways for IB students:
-
A 4 is commonly treated as a passing grade, but “passing the diploma” depends on the full set of diploma rules (not one number in isolation).
-
A 5 or 6 is already a strong result in most contexts. The IB is designed so that top-band performance is genuinely difficult.
For how universities and counselors sometimes translate these grades into more familiar systems, see IB Grade to GPA & Letter Grade Conversion.
Why IB grades are not “just percentages”
Many students try to translate the IB into the logic they already know: “What percent is a 6?” The honest answer is: it depends.
The IB uses criterion-referenced assessment. That means you’re graded against published standards and markbands, not against how other students did in your class. After marking, raw marks are mapped onto grades using grade boundaries.
This is why two things can be true at once:
-
One year, a 7 in a subject might require a higher raw mark.
-
Another year, that requirement might drop slightly.
The goal is fairness across exam sessions: if a paper was unusually tough, boundaries can shift to keep the grade meaning stable.
To make this concrete for your own revision, you can combine your practice marks with boundaries using the IB Grade Calculator. That’s often the moment the grading system stops feeling abstract.
IB grade boundaries (and why they change)
IB grade boundaries are the cut-offs that convert your final mark into a 1-7 grade. They vary by:
-
Subject
-
Level (SL vs HL)
-
Timezone/session
-
Exam difficulty and examiner judgement
Students sometimes find this unsettling because it feels like a moving target. But boundaries are less “moving goalposts” and more “calibration.” They’re one of the ways the IB tries to keep a 6 in your subject meaning roughly the same thing from one cohort to the next.
If you want a student-friendly explanation of how to use boundaries without obsessing over them, read IB Grade Boundaries 2025 Guide.
The IB core: TOK, EE, and CAS
The IB Diploma isn’t only six subjects. It’s also the core, and it affects your final point total.
TOK and EE: up to 3 bonus points
-
Theory of Knowledge (TOK) is graded A to E.
-
The Extended Essay (EE) is graded A to E.
-
Together, they can contribute 0 to 3 bonus points to your diploma total.
Those bonus points can quietly change everything. Two students with the same six subject grades can end up with different totals because of TOK/EE performance.
For step-by-step support, the IB Extended Essay Guide: Structure, Research Question, Rubric is a strong starting point, and How to Use TOK to Enhance Your Extended Essay helps you connect the two.
CAS: required, not graded
CAS isn’t awarded a grade, but it must be completed to earn the diploma. Think of it like a locked door: you can have the points, but you still need the key.
If you’re a parent reading this: CAS stress often comes less from the activities and more from documentation and reflection. A simple weekly reflection habit prevents end-of-year panic.
Total IB Diploma points and basic awarding rules
The maximum IB score is 45:
-
42 from six subjects (6 × 7)
-
3 from TOK/EE bonus points
To earn the IB Diploma, students generally must:
-
Earn at least 24 total points
-
Complete CAS
-
Meet distribution requirements (for example, avoiding very low subject grades)
Schools also track several failing conditions (for example, extremely low grades in a subject or certain combinations in the core). In other words, the diploma is about the whole profile, not just the total.
If you want context for how the whole programme is structured, see What is the IB Program & International Baccalaureate Grading System.
Predicted grades: why they matter (and how to improve them)
Predicted grades are teacher estimates of the final IB grade you’re likely to achieve. Universities may use them for conditional offers, and schools use them to guide intervention.
The best way to improve predicted grades is boring, but effective: produce better evidence. Timed practice. Consistent marking. Clear progress.
Two helpful resources:
RevisionDojo is built around that evidence loop. You revise with Study Notes, lock in recall with Flashcards, then pressure-test with the Questionbank and Mock Exams. When answers miss the mark, AI Chat helps you fix misconceptions quickly, and the Grading tools show you what the rubric rewards. If coursework is your bottleneck, the Coursework Library and Tutors fill the gaps with examples and human strategy.
Common misunderstandings about IB grading
-
“A 6 means 60%.” In the IB, a 6 is a grade descriptor supported by boundaries. It doesn’t map cleanly to one universal percentage.
-
“If I mess up one subject, I fail everything.” Not always. The diploma is conditional on total points and specific constraints.
-
“You need a 7 in everything.” You really don’t. Many university offers are built around realistic combinations of 5s, 6s, and a couple of 7s.
Re-marking and resits: what students should know
If your final grade feels off, schools can submit a re-mark request (often called a remark). This can sometimes change a grade, but it’s not a guaranteed correction. It’s a second look under formal procedures.
Resits are typically available in the next exam session. The bigger decision is strategic: will a resit improve your options meaningfully, or is your time better spent strengthening coursework, applications, or first-year readiness?
Closing: make the IB grading scale work for you
The IB grading scale isn’t trying to be mysterious. It’s trying to be consistent across countries, schools, and exam sessions. Once you see the structure: 1 to 7 grades, TOK/EE bonus points, boundaries that calibrate difficulty; your job becomes clearer: build the kind of evidence the system rewards.
If you want that process to feel simpler, make it measurable. Use the IB Grade Boundaries page to understand your target band, the IB Grade Calculator to convert practice marks into realistic outcomes, and RevisionDojo’s Study Notes, Flashcards, AI Chat, Grading tools, Questionbank, Mock Exams, Predicted Papers, Coursework Library, and Tutors to close the gap.
In the IB, clarity is a competitive advantage. Start there, and the points usually follow.