How the HSC ATAR is calculated (NSW, 2026)
In NSW, your ATAR is built from your scaled marks in 10 units — your best 2 units of English (always counted) plus your best 8 remaining units. UAC adds these into an aggregate out of 500, ranks every student, and converts that rank into your ATAR. Your raw HSC marks are scaled first, so how your subjects scale matters as much as the marks themselves.
What counts towards your ATAR?
Your ATAR is based on 10 units of scaled marks: your best 2 units of English (these are always included, even if English is one of your lower results) plus your best 8 units from your remaining ATAR courses. Most courses are worth 2 units, so this is typically your best five subjects, one of which must be English.
Those 10 units of scaled marks are added to form an aggregate out of 500. UAC then places every student in order of their aggregate and turns that position into an ATAR — a rank between 0 and 99.95.
Why are HSC marks scaled?
A mark in one course isn’t directly comparable to the same mark in another, because courses attract different groups of students. Scaling estimates what your marks would have been if every course had been studied by the same students, adjusting each course’s mean, spread and maximum accordingly.
The practical effect: courses taken by stronger overall cohorts (for example, the highest‑level mathematics and sciences) tend to scale up, while others scale down. This is set by UAC’s Technical Committee on Scaling, not by NESA.
How do the Mathematics extension courses count?
Mathematics Extension 1 counts as 1 unit when paired with Mathematics Advanced, but as 2 units (the mark is doubled) when paired with Extension 2. If you complete Advanced, Extension 1 and Extension 2, your Mathematics Advanced result is not included — only the extension results count. The same staged rule applies to English: you must complete Advanced to count Extension 1.
Are you eligible for an ATAR?
To receive an ATAR you must satisfactorily complete at least four subject areas, with enough ATAR‑eligible units to form the 10‑unit aggregate (including your 2 units of English). Vocational and some other courses may not all count — check your specific pattern of study with UAC.