Compared to other curriculums in Australia such as the VCE, HSC, SACE, QCE or WACE, the way you get your score is quite simple. All students received a score out of 45 which was then converted to an ATAR one to one.
However, this changed in 2022 when ACTAC (the Australasian Conference of Tertiary Admissions Centres) adopted a new way to convert IB scores to ATAR as they believed the IB score out of 45 did not provide enough granularity for fair comparison to the rest of the Australian curriculums. In December 2022, the first cohort of students received their IBAS.
In this blog we will go over everything you need to know in 2025 about your IB score, IBAS and ATAR.
What is your IB score?
In the IB, all students receive a score out of 45. Your score is comprised of two main components.
- 42 / 45 points = score out of 7 for 6 subjects
- 3 / 45 points = score for Theory of Knowledge and Extended Essay
❗For a full understanding of how the IB is graded, check out this blog.
The threshold to get a 7 for each subject changes every year and varies from subject to subject.
Why is the IB score different to ATAR?
IB is a score while ATAR is a rank: only a certain number of students can receive a 99.95 ATAR, while theoretically, there is no limit to how many students can obtain a perfect 45 out of 45 IB score.
What is your IBAS score?
Your IB Admissions Score (IBAS) is a “fine-tuning” of your IB Diploma total. Whereas the Diploma itself gives you an integer between 24 and 45, the IBAS adds a decimal (in 0.25-point steps) to show exactly where you sit within each grade band. For example, if you score a 41 on your Diploma and your subject marks place you high in each band, you might end up with a 41.75 IBAS rather than just 41. This extra precision helps universities see the small differences between candidates and converts into an ATAR-equivalent rank that feeds directly into your tertiary application.
How is the IBAS calculated?
The IBAS is calculated by taking your raw IB score and then for each subject determining a more accurate score than just out of 7.
Your IBAS score will never be lower than your raw IB score
For each of your six subjects, the IBO provides your underlying scaled total mark (STM out of 100) alongside the published grade boundaries. The STM tells exactly where your mark sits within that band. For instance, for Biology HL students had to get a 76 to get a 7.
To calculate your IBAS, first look at where your raw marks sit within each subject’s grade band—if the band for a 6 in Biology is 62–75 and you scored a 74, you’re near the top; if you scored a 63, you’re near the bottom. Imagine that band as a 0.0–1.0 scale and convert your score into a fraction (e.g. 0.67 for 66). Do this for all six subjects, then average those six fractions to get one number—say 0.62. Round that average to the nearest quarter (0.50 or 0.75), and finally add it to your whole-number IB total (for example, 41 + 0.75 = 41.75) to arrive at your fine-tuned IB Admissions Score.
Essentially the IBAS will provide a more accurate reflection of how well a student did in a subject.
How is the IBAS converted to ATAR?
For all six subjects, students will receive a revised score to 0.25 decimal places.
Every 0.25 decimal places is mapped to an ATAR. You can see the official mappings for 2025 here.
Some key figures:
- To get a 99.95 ATAR, you needed to score at least 45.50 in the IB (a 45 will no longer equate to a perfect score).
- To get a 95 ATAR, you needed to score at least 35.50 in the IB.
- To get a 90 ATAR, you needed to score at least 39.00 in the IB.
When you are applying for universities and they require your ATAR, they will take your IBAS score.
Enter your IBAS score and we will show you your converted ATAR.
Converting subject scores by state
For some university degrees, they will have a minimum score you must get in a specific subject. Below we will show the conversion.
They will use your raw IB score out of 7 (as opposed to your scaled score with IBAS)
For NSW
For VIC
Comparing distribution of scores in IB vs ATAR
Australian IB results in November 2024
The IB just released from the November 2024 exams. These are the exams that Australian students participate in.
Here is a state by state breakdown
Comparatively to the rest of the world, Australia is a very strong cohort:
Australia represented only 14% of the total students in the November exam but represented over 34% of the students in the November cohort
Is it easier to get a higher ATAR in IB or Australia?
We can first compare averages. A 34 IB score is converted to an ATAR of 88.00. The average ATAR does change from curriculum to curriculum, but it is approximately 70.00. This means on average, students do much better in the IB.
What about for students who do exceptional well. We can use the 40 IB score as our threshold which converts to a 96.05 ATAR. 593 out of 3,047 students received this mark or above, which translates to ~19.4% of students. This much greater than ~4% of students who complete Australian curriculum who would achieve above a 96.05. Even on a global level, 8% of students achieved above a 40 or above.
Is it easier to get a 99.95 by doing the IB?
The IB has stopped releasing the exact number of students who received a 45. The last time they did release this number was in 2023.
In 2023, 53 students in Australia got a 99.95 out of 2,646 students who took the IB. That is ~2% success rate which is way higher odds than if you completed one of the local curriculums in Australia where only 0.05% of students get this grade.
In 2023, there were 179 students who received a 45 out of 192,867 students. That is a success rate of 0.09%, much closer to that of the Australian curriculums.
Although Australian students made up only about 1.3% of all IB Diploma candidates in 2023, they earned nearly 30% of the perfect 45 scores.
Australian over-representation in scores of 45 has not just happened in 2023.
