In short: each calculator turns your subject results into scaled scores using last year's official scaling data, adds them the way your state does, and reads the ATAR from the official 2025 aggregate table. Victoria, South Australia and Western Australia use full official tables. New South Wales uses UAC's published percentile points. Queensland has no official aggregate to ATAR table, so that result is a modelled estimate.
What every calculator does
- Converts each subject result to a scaled score. Scaling puts every subject on one level so they can be added fairly. We use the scaling published for students who finished Year 12 in 2025.
- Adds the scores your state's way. Each state counts a different number of subjects and gives different weights. The rules we apply are printed under every result.
- Reads the ATAR from the 2025 table. Where the admissions centre publishes a full aggregate to ATAR table, we use it directly.
- Shows its working. Every result lists which subjects counted, their scaled scores, the aggregate, the source and whether the result is official data or an estimate.
Nothing you type is sent anywhere. The calculators run in your browser, and your last inputs are saved only on your own device so you can come back to them.
Data used for each state
| State | Scaling data | Aggregate to ATAR | Label |
|---|---|---|---|
| VIC (VCE) | VTAC 2025 Scaling Report: scaled study scores at 20, 25, 30, 35, 40, 45 and 50 for 95 studies | VTAC 2025 Aggregate to ATAR Table (every ATAR from 30.00 to 99.95) | Official data |
| NSW (HSC) | UAC 2025 scaling report, Table A3: HSC and scaled marks at the 25th, 50th, 75th, 90th and 99th percentiles for 85 courses | UAC Tables A9 and 3.2: aggregate for 21 published ATAR points | Estimate |
| QLD (QCE) | QTAC ATAR Report 2025: raw and scaled results at five percentiles, Applied grades and VET levels | None published. Modelled from the QTAC 2025 ATAR distribution | Estimate |
| SA and NT (SACE, NTCET) | You enter your scaled scores | SATAC 2025 university aggregate to ATAR (every 0.05 from 0 to 90) | Official data |
| WA (WACE) | You enter your scaled scores. TISC 2025 course statistics shown for reference | TISC official ATAR calculator for 2025, read at every whole TEA from 150 to 430 | Official data |
Known limits, state by state
Victoria
VTAC publishes scaled scores rounded to whole numbers at seven points. We join those points with straight lines, so a study score of 33 gets a scaled score between the published 30 and 35 values. VTAC works to two decimal places, so results can differ by a small amount. Below a study score of 20 the scaled score is estimated. VTAC counting limits on English and Mathematics studies are not checked.
New South Wales
UAC states that its Table A3 is not a one to one conversion: the same HSC mark can lead to a range of scaled marks. UAC also publishes the 2025 aggregate for selected ATARs only, so ATARs between those points are read in a straight line. Both make the NSW result an estimate.
Queensland
QTAC does not publish a table that turns a Tertiary Entrance Aggregate (TEA) into an ATAR. Our model assumes a student holds about the same rank in every subject, then matches the average of the best five scaled results to the share of ATAR-eligible students above it in 2025. Expect an error of several ATAR points.
South Australia and the Northern Territory
The flexible option (the last 30 credits) is simplified: the fourth 20-credit subject counts in full and the last 10 credits come from your best 10-credit subject or half of a fifth 20-credit subject. Precluded combinations, counting restrictions and Recognised Studies are not checked.
Western Australia
The 10% bonus for Mathematics Methods, Mathematics Specialist and one language applied to 2025 ATARs; TISC has postponed its removal to 2027 at the earliest. Between whole-number TEA values the ATAR is read in a straight line.
What no calculator can do
- Know this year's scaling. Scaling is recalculated every year from that year's students and is released with results. Every calculator, ours included, uses last year's numbers.
- Add adjustment factors. Bonus points for subjects, location or equity schemes change your selection rank for a course, not your ATAR. See ATAR vs selection rank.
- Fix the inputs. An estimate is only as good as the marks you type in. Trial and school marks often move before final results.
How we keep the data current
When an admissions centre releases a new scaling report, we load the new table, test known cases against it and log the change on the data updates page. The year of the data is shown under every result.
Questions or a mistake to report? Email info@atarcalculatoronline.com or use the contact page.