Every number on pay-calculator.au comes from one of two places: a named primary document, or a tax engine that implements those documents in code. Nothing is typed into a page from memory, nothing is carried forward from last year without being flagged, and every page states when its figures were last verified. This page sets out the whole process.
Which source documents does the site use?
The site works from primary publications only: the ATO for tax and withholding, the Fair Work Ombudsman for entitlements, and Moneysmart (ASIC) for cross-checks. The main documents behind the 2026-27 figures are:
| Document | What it feeds | Status for 2026-27 |
|---|---|---|
| ATO, Tax rates for Australian residents | Resident brackets on every calculator, including the 15% first marginal rate from 1 July 2026 | Last updated 1 June 2026 |
| ATO, Tax rates for foreign residents; Tax rates for working holiday makers | Foreign resident and 417/462 visa scales | Last updated 1 June 2026 |
| ATO, Study and training support loans rates and repayment thresholds | HECS-HELP marginal repayment bands and the $69,528 threshold | Last updated 30 June 2026 |
| ATO, Schedule 5 (NAT 3348): back payments, commissions, bonuses | Bonus and backpay withholding methods | Published 17 June 2026, applies from 1 July 2026 |
| ATO, Schedule 7 (NAT 3351): unused leave payments on termination | Tax withheld from leave paid out when you leave a job | Published 17 June 2026, applies from 1 July 2026 |
| ATO, Schedule 11: employment termination payments | ETP withholding, caps and rates | Caps confirmed for 2026-27 |
| ATO, Super guarantee rates and thresholds | The 12% super guarantee and maximum contribution base | Last updated 17 April 2026 |
| Fair Work, National Employment Standards; Redundancy pay; Annual leave | Leave accrual, redundancy weeks, notice, final pay rules | Annual leave content last updated 25 March 2026 |
The full annotated list, with links to each document, is on the official sources page. Each calculator and guide also ends with a Sources section naming the specific documents behind that page.
What does computed, not typed, mean?
All figures on the site render from one tax engine. The engine holds the published 2026-27 brackets, thresholds and rates as constants, verified against the documents above, and every table, worked example and calculator result is computed from it when the page renders. No page contains a hand-typed tax figure.
This matters because hand-typed numbers fail silently. A site with 40 pages of typed tables has 40 places for last year’s rate to hide. With one engine, a verified rate feeds every page at once, and an error, if one occurs, is at least an error you can find and fix in one place. The table below is itself an example: the tax amounts are computed by the engine inside this page, not typed into it.
| Taxable income | Income tax before offsets (2026-27) | Medicare levy | Combined |
|---|---|---|---|
| $60,000 | $8,520 | $1,200 | $9,720 |
| $90,000 | $17,520 | $1,800 | $19,320 |
| $120,000 | $26,520 | $2,400 | $28,920 |
Figures shown are resident income tax before the Low Income Tax Offset, plus the 2% Medicare levy, for a single person with no study loan. Source: ATO, Tax rates for Australian residents, 2026-27.
How is a figure verified before it appears?
- The primary document is read in full, not summarised from secondary coverage.
- Its title, NAT number where one exists, and published or last-updated date are recorded in the research notes that sit behind the site.
- The rule is implemented in the engine following the published method step by step, then checked against the worked examples the ATO prints in the schedule itself.
- Where two official sources disagree, the more recently updated and more authoritative one wins, and the conflict is recorded. Example: in July 2026 Moneysmart still showed the old non-concessional super cap while the ATO page showed the 2026-27 figure, so the ATO figure is used.
- The page is dated. A figure without a date is treated as unverified.
What does the last-verified date mean?
Last verified means a person checked the page’s figures against the current source documents on that date. It is not an automatic timestamp and it does not update when unrelated text changes. If a page says last verified 23 July 2026, the rates on it matched the ATO’s published 2026-27 documents on 23 July 2026.
What happens when the ATO moves a rate?
The update process runs in a fixed order:
- The new document is read and its figures recorded, with the publication date.
- The engine constants are updated. Because every table renders from the engine, every affected page updates at once.
- Worked examples and prose that quote specific amounts are re-checked against the new output.
- The affected pages get a dated note stating what changed, for example: updated when the ATO published the 2026-27 low-income thresholds.
- The last-verified date is set to the date of the check, not the date of the ATO release.
The heavy update lands each June and July, when the ATO publishes the withholding schedules for the new financial year and Fair Work applies the Annual Wage Review. The editorial policy describes that cadence.
What about figures the ATO has not published yet?
They are flagged, not guessed. Early in a financial year some thresholds lag: as at 23 July 2026 the ATO has not published the 2026-27 Medicare levy low-income thresholds, so the site uses the 2025-26 amounts and says so on the pages that rely on them. When the new figures are released, the engine is updated and the note is replaced with a dated correction line.
What this methodology cannot do
It can make the published rates exact. It cannot make an estimate personal. The calculators do not know your deductions, offsets beyond the standard ones, family situation or private health cover, and withholding is always an estimate of tax, not the tax itself. Nothing on the site is personal advice, and genuinely complex situations belong with a registered tax agent. The about page and terms of use spell out those limits, and the content is written under the byline described on the page for Marcus Kelleher.