WACE Chemistry has been a top-three scaling subject in WA for as long as TISC has published the data. The most recent (2025) scaling report places Chemistry behind only Mathematics Specialist, with a typical scaling lift of 7 to 9 marks at the median.
The question students rarely ask: what raw mark in Chemistry do I actually need to hit my target ATAR? Below is the realistic translation, with the caveats that scaling cannot be guaranteed in advance.
What "Chemistry scales by 8" actually means
The TISC scaling report shows that, in 2025, a raw mark of 70 in Chemistry scaled to approximately 78.7. A raw mark of 80 scaled to approximately 88. A raw mark of 90 scaled to approximately 96. The scaling is non-linear: it is larger at the top and smaller at the bottom.
| Raw Chemistry mark | Approx. scaled mark (2025) | Lift |
|---|---|---|
| 50 | ~57 | +7 |
| 60 | ~68 | +8 |
| 70 | ~78.7 | +8.7 |
| 75 | ~83.5 | +8.5 |
| 80 | ~88 | +8 |
| 85 | ~92 | +7 |
| 90 | ~96 | +6 |
The lift is significant but flattening at the top. The reason: very high raw scorers are already at the upper bound, and there is less room to scale up.
What raw Chemistry mark do you need at each ATAR?
Assume Chemistry is one of your top 4 scaled subjects. Realistic targets, given typical other-subject performance:
| Target ATAR | Raw Chemistry needed | If your other 3 are strong |
|---|---|---|
| 85 | ~55-60 | You can drop to 50 with strong scaled subjects elsewhere |
| 90 | ~65-70 | You can drop to 60 with Specialist + Methods |
| 95 | ~75-80 | Tight margins; ~5-mark improvements matter |
| 98 | ~83+ | Chemistry becomes load-bearing |
| 99.5 | ~88+ | Top 1% raw needed |
Why Chemistry scales so well
Two reasons. The first is cohort: students who take Chemistry tend to score well in their other subjects too. TISC's scaling algorithm rewards subjects whose students are above-average overall, and Chemistry students are.
The second reason is the difficulty of the syllabus. The SCSA Chemistry syllabus has 47 dot points across two units. The exam is content-rich, calculation-heavy, and time-pressured. Students who score well have demonstrated genuine subject mastery, and TISC's scaling reflects that.
What this means for subject choice
Chemistry is the single best ATAR pickup for STEM-bound students who can score in the top half of the cohort. If you can confidently target 70+ raw in Chemistry, it almost always lifts your ATAR more than another subject would.
Chemistry is the wrong choice if you are scoring under 50 raw consistently in school tests. The scaling does not save you from a low raw mark. A 45 raw in Chemistry scales to roughly 50, which is still below the WA median.
Cross-subject scaling check
How does Chemistry compare to other common ATAR subjects?
| Subject | Approx. lift at 70 raw (2025) |
|---|---|
| Mathematics Specialist | ~+10 (highest) |
| Chemistry | ~+8.7 |
| Physics | ~+8.4 |
| Mathematics Methods | ~+5 to +6 |
| Human Biology | ~+2 to +3 |
| English | ~0 to -1 |
| Mathematics Applications | ~-3 to -5 |
What to actually do this week
- Plug your projected raw Chemistry mark into our ATAR calculator. Try three values: pessimistic, realistic, optimistic. See the impact on your ATAR.
- Read the most recent TISC scaling report (search "TISC scaling 2025") for full per-subject tables. The actual numbers shift slightly each year.
- Set your target raw Chemistry mark for end of Year 12 now. Write it on your study plan. Aim 5 marks higher in your school tests so you have margin on exam day.
If you want help mapping subject scaling to a target ATAR with a per-subject raw mark plan, book a free trial class. Our Year 12 Chemistry students get a personalised target plan in their first lesson.