How Is the SACE ATAR Calculated in South Australia?

The South Australian ATAR involves two bodies working in sequence. The SACE Board runs senior secondary assessment — it sets curriculum, moderates school assessments, and issues your Stage 2 grades (A+ to E). SATAC (South Australian Tertiary Admissions Centre) then takes those results, applies a scaling process using the Equal Achievement Principle, calculates your university aggregate from your best 90 credits, and converts it into an ATAR.

The same system applies to Northern Territory students completing the NTCET (Northern Territory Certificate of Education and Training). NTCET uses SACE subjects and SATAC scaling, so this calculator works for both SA and NT students.

The Calculation Process

1. School and external assessment: For each Stage 2 Tertiary Admissions Subject (TAS), you receive marks for school-assessed components (typically 70%) and an externally assessed component (typically 30%, usually an exam).
2. Raw score: Internal marks (out of 10.5) plus external marks (out of 4.5) give a raw score out of 15 for each 20-credit subject.
3. Scaling: SATAC scales all raw scores using the Equal Achievement Principle — comparing how students in each subject perform across all their other subjects. Each subject receives a scaled score out of 20.
4. University aggregate: SATAC selects your best 90 credits of scaled scores. The maximum aggregate is 90.
5. ATAR: SATAC ranks all eligible SA and NT students by aggregate and assigns ATARs from 99.95 down to 30.00.

Key difference from other states: SATAC does not publish official per-subject scaling tables. The scaling process uses proprietary cohort data and the Equal Achievement Principle. Any scaling figures you see online (including in this calculator) are approximations based on historical patterns, not official SATAC data.

Understanding the 90-Credit Aggregate

The 90-credit aggregate is the foundation of your SACE ATAR. Most Stage 2 subjects are worth 20 credits each, so the typical aggregate structure looks like this:

Best 4 subjects at full value (4 x 20 credits = 80 credits) plus half of your 5th subject (10 credits) = 90 credits total. Alternatively, your best 4 subjects (80 credits) plus your Activating Identities and Futures (AIF) subject (10 credits) = 90 credits.

The maximum aggregate is 90 — achieved by scoring 20/20 in every subject across 90 credits. In practice, an aggregate of about 83.5 is needed for an ATAR of 99.00, and about 60.0 for an ATAR of 80.00.

The half-subject trap: Your 5th subject only contributes half its scaled score to the aggregate (10 out of 20 credits). This means improving your 4th subject by 1 scaled point is worth twice as much as improving your 5th subject by 1 point. Focus your study effort on your top four subjects.

The AIF and Research Project

From 2026, Activating Identities and Futures (AIF) replaced the former Research Project B as a compulsory 10-credit Stage 2 subject. AIF is required for SACE completion and ATAR eligibility. It contributes 10 credits to your aggregate.

Because AIF is only 10 credits, its contribution to your aggregate is half that of a full 20-credit subject. A strong AIF result can help — but your four main 20-credit subjects are always more important.

How SATAC Scaling Works

SATAC uses the Equal Achievement Principle: if two students achieve equally well across all their subjects, they should receive the same university aggregate regardless of which specific subjects they chose. To make this work, SATAC examines how students in each subject perform across all their other subjects.

If Specialist Mathematics students tend to perform very strongly in their other subjects, that signals the Specialist Maths cohort is academically powerful — and Specialist Maths scores scale up. If a subject’s cohort tends to underperform elsewhere, that subject’s scores scale down.

Subjects That Scale Up

Subjects That Scale Down

How to Use the SACE ATAR Calculator

Step 1: Select Your Subjects

Choose your Stage 2 subjects from the grouped dropdown. Include your AIF or Research Project (listed under Cross-Disciplinary). The calculator starts with five rows — add more if needed.

Step 2: Select Your Grades

Choose your grade (A+ through E) for each subject from the grade dropdown. If you haven’t received final grades yet, use your most recent assessment feedback as a guide.

Step 3: Calculate and Review

Hit “Calculate My ATAR” to see your estimated ATAR, university aggregate, and a breakdown of how each subject contributes. The calculator automatically picks your best 90 credits — including partial credit from your 5th subject if applicable.

Tips for SA and NT Students

Your top four subjects matter most. They contribute 80 of your 90 aggregate credits at full value. Your 5th subject only adds half its scaled score. Concentrate your effort where it counts — a one-grade improvement in your 4th subject is worth more than a one-grade improvement in your 5th.

English Literary Studies scales better than English. If you’re a strong reader and writer, English Literary Studies (A+ scaled: 18.2) outperforms standard English (17.5). The gap widens at lower grades.

Specialist Maths is the highest-scaling subject in SACE. An A+ in Specialist Maths gives the maximum possible scaled score of 20.0. But you need genuine mathematical ability — a C in Specialist Maths (scaled: 12.0) is worth less than an A in General Maths (scaled: 15.2).

Don’t ignore the AIF. At 10 credits, it contributes less than a full subject, but a strong grade can still add 7-8.5 points to your aggregate. That’s the difference between one ATAR bracket and the next.

NT students receive the same ATAR. NTCET students are ranked alongside SA students in the same SATAC pool. The same scaling, aggregation, and ranking process applies.

Calculators for other states: Victoria (VCE) · NSW (HSC) · Queensland (QCE) · Western Australia (WACE) · Tasmania (TCE) · ACT (BSSS) · All states