IB Grade Boundaries
The published May 2025 boundaries, subject by subject: what a 7 took, where the 4 band started — in one table, with a detailed guide for each subject.
May 2025 boundaries — every subject
Figures are percentages of the total mark. Source: our published guide for each subject; the IB releases the official boundaries to schools once a session has been marked.
| Subject | Level | 7 | 6 | 5 | 4 | Detailed guide |
|---|---|---|---|---|---|---|
| Mathematics: Analysis & Approaches | SL | 80-100 | 67-79 | 53-66 | 37-52 | Guide |
| Mathematics: Analysis & Approaches | HL | 79-100 | 65-78 | 52-64 | 37-51 | Guide |
| Mathematics: Applications & Interpretation | SL | 82-100 | 70-81 | 57-69 | 42-56 | Guide |
| Mathematics: Applications & Interpretation | HL | 77-100 | 65-76 | 52-64 | 39-51 | Guide |
| Biology | SL | 76-100 | 64-75 | 52-63 | 40-51 | Guide |
| Biology | HL | 79-100 | 64-78 | 50-63 | 35-49 | Guide |
| Chemistry | SL | 75-100 | 65-74 | 55-64 | 44-54 | Guide |
| Chemistry | HL | 77-100 | 64-76 | 52-63 | 40-51 | Guide |
| Turkish A: Literature | SL | 76-100 | 65-75 | 53-64 | 42-52 | Guide (in Turkish) |
Official source: International Baccalaureate Organization · Last checked July 2026 · This table is updated when a new session's boundaries are released.
Frequently asked questions
What are IB grade boundaries?
They are the minimum percentage totals that decide your final 1-7 grade in each IB subject. The IB publishes them per subject and per level (SL or HL) after each exam session has been marked, and they can move from one session to the next.
What did you need for a 7 in Math AA SL in the May 2025 session?
In the May 2025 session, Mathematics: Analysis & Approaches SL required a total in the 80-100% band for a 7.
Do grade boundaries change every year?
Yes. Boundaries are re-set according to how difficult each session turned out to be, so the published May 2025 figures in this table are a planning guide rather than a guarantee for a future session. The table is updated when the IB releases a new session.
How do I estimate my grade from these boundaries?
Work out your percentage total on a past paper or mock, then read it against the bands for that subject and level. Because the bands shift between sessions, treat a result that sits within two or three percentage points of a boundary as the band below it rather than the one above.
Are these the official IB boundaries?
The figures come from our own published subject guides, each linked in the table, and reflect the May 2025 session. The IB is the official source and releases boundaries to schools after grading; where a school's coordinator gives you a different figure for your session, that figure is the one to use.
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