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Are you in the process of preparing for your IB Biology exams or writing your IA and wondering how you can get the best possible grade? This post is here to help give you an idea of the grade boundaries for Biology so you can plan yourself accordingly. Keep in mind that these values change from session to session and hence are only an indicator of the approximate marks you would need for a certain grade, but feel free to use this guide as a planning tool!
IB Biology Grade Boundaries
The following grade boundaries are based on official IB May 2025 grade boundaries.
Standard level
Points needed | |||||
|---|---|---|---|---|---|
Grade | Paper 1A | Paper 1B | Paper 2 | Practical Work | Final grade (%) |
1 | 0-7 | 0-1 | 0-5 | 0-3 | 0-12 |
2 | 8-14 | 2-3 | 6-10 | 4-6 | 13-25 |
3 | 15-17 | 4-5 | 11-17 | 7-10 | 26-38 |
4 | 18-19 | 6-8 | 18-25 | 11-13 | 39-51 |
5 | 20-21 | 9-12 | 26-32 | 14-16 | 52-63 |
6 | 22-23 | 13-15 | 33-40 | 17-19 | 64-76 |
7 | 24-30 | 16-25 | 41-50 | 20-24 | 77-100 |
Higher level
Points needed | |||||
|---|---|---|---|---|---|
Grade | Paper 1A | Paper 1B | Paper 2 | Practical Work | Final grade (%) |
1 | 0-10 | 0-2 | 0-6 | 0-3 | 0-12 |
2 | 11-20 | 3-5 | 7-13 | 4-6 | 13-24 |
3 | 21-22 | 6-8 | 14-22 | 7-10 | 25-35 |
4 | 23-26 | 9-13 | 23-34 | 11-13 | 36-48 |
5 | 27-29 | 14-19 | 35-45 | 14-16 | 49-61 |
6 | 30-33 | 20-24 | 46-57 | 17-19 | 62-75 |
7 | 34-40 | 25-35 | 58-80 | 20-24 | 76-100 |
We hope that this guide helps you in planning your studies and IA writing. For examples of how to structure a good biology IA check out these blog posts (1- topic ideas, 2- how to get started, 3- format and structure, 4- top 10 mistakes to avoid). Also, make sure to visit Clastify for tons of free IA examples. Good luck!
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