GST calculator.
Add 10% GST to a price, or extract it from a GST-inclusive total with the ÷11 rule: both directions, instantly.
Open the calculator →BAS calculator.
Sales and purchases in, labels 1A and 1B out, and whether the quarter ends in a payment or a refund.
Open the calculator →GST threshold calculator.
Monthly turnover in, projected 12-month turnover out, and how close you are to the compulsory $75,000 line.
Open the calculator →GST backdating calculator.
Credits on past purchases versus GST owed on past sales, see whether backdating your registration pays.
Open the calculator →Margin & markup calculator.
Cost price to GST-inclusive shelf price, with the markup-to-margin conversion everyone gets wrong.
Open the calculator →Day rate calculator.
Work backwards from your target income and costs to the day rate you should quote, ex GST and on the invoice.
Open the calculator →About these calculators.
How is GST calculated in Australia?
GST is a flat 10%. To add it, multiply the ex-GST price by 1.1. To extract it from a GST-inclusive total, divide the total by 11. That's the GST portion. The GST calculator does both directions.
Are these calculators a substitute for advice?
No. They're estimates built on the standard 10% GST arithmetic, for general information. Your actual BAS and registration decisions depend on your circumstances; a registered agent reviews the real numbers before anything is lodged.
Is anything I type stored?
No. Every calculator runs entirely in your browser. Nothing you enter is sent to us or anyone else.
Related guides: How to calculate GST · What is a BAS? · Do I need to register for GST?
Numbers say it's time? Registration takes ~4 business hours.
Lodged by Registered BAS Agent 25972850 · tax deductible · free help on 1800 546 526.