Understanding IB Grade Boundaries (May 2025): How Your Final Grades Are Set
When your IB results are released, the grades you see are not arbitrary. They are determined using official IB grade boundaries, which convert your raw marks into final grades from 1 to 7. For students in the May 2025 session, knowing how these boundaries work can help you understand your results clearly—and decide what to do next.
All grade boundaries are set and applied by the International Baccalaureate.
What Are IB Grade Boundaries?
IB grade boundaries are the minimum mark thresholds required to earn each grade in a subject.
They:
- Define the cut-off for grades 1 through 7
- Are determined after exams are marked
- Are based on global student performance in that specific session
Their purpose is to keep grading fair, even if one year’s exams are harder or easier than another’s.
How Grade Boundaries Actually Work
After marking is complete, IB examiners review how students worldwide performed. They then set boundaries so that grades reflect achievement relative to exam difficulty, not just raw percentages.
For example:
- A very challenging paper may have lower boundaries
- A more accessible paper may have higher boundaries
Each subject, level (HL or SL), and exam session has its own unique boundaries.
Where to Find IB Grade Boundaries for 2025
After results are released:
- Schools receive the official grade boundaries directly from the IB
- Some schools choose to share them with students—ask your IB coordinator
