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Business calculators: for the numbers side of starting out

Six free tools built for new and small Australian businesses. Instant, private (nothing you type leaves your browser), and each one linked to the plain-English guide behind it.

GST Calculator

Put 10% on top of your price, or find the GST hiding inside a total, the two sums every new invoice needs.

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BAS Calculator

Sales and GST-carrying costs in, an estimate of your activity statement out, payment or refund, in plain words.

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GST Turnover Calculator

How close is your ABN to the $75,000 line where GST becomes compulsory? Check your run rate.

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GST Backdating Calculator

Started trading before sorting the GST? Weigh the credits waiting against the catch-up GST owed.

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Markup & Margin Calculator

Cost price to customer price without mixing up the two percentages. GST layer added last, where it belongs.

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Day Rate Calculator

The salary-to-day-rate conversion done properly: real costs, realistic billable days, GST separated out.

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About these tools

Are the results advice?

No. They're estimates using the standard 10% GST arithmetic, for general information. Registration and lodgement decisions depend on your circumstances; a registered tax agent reviews the real thing before anything is lodged.

Is what I type stored anywhere?

No, every calculator runs entirely in your browser. Nothing you enter is sent to us or anyone else.

Why does an ABN service host GST calculators?

Because the two arrive together: most new ABN holders hit the GST questions (charge it or not, register or wait, what to quote) in their first months. The tools answer the numbers; the guides linked from each one answer the rules.

Related guides: Do I need to register for GST? · ABN vs ACN · Do I need an ABN?

Numbers done? The ABN is the next step.

Registered Tax Agent 26076969 · usually same-day · free help on 1800 546 526.

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