AusCalc is a free suite of Australian tax calculators built for sole traders, freelancers, contractors and employees. Work out sole trader tax, PAYG withholding, GST, HECS-HELP repayments, super, salary sacrifice, contractor day rates and BAS deadlines in seconds. Every calculation runs in your browser, so nothing is stored and there is no signup. Updated for the 2025-26 and 2026-27 ATO rates.