GST & Profit Calculator for Australian Small Businesses
Use this GST and profit calculator to estimate your revenue excluding GST, expenses excluding GST, GST collected, GST paid, net GST position, and estimated profit. It is a quick way to get clearer on your numbers before lodging BAS or reviewing business performance.
This GST calculator for Australia helps small business owners quickly work out GST payable or refundable, and understand profit on an ex-GST basis. If you are preparing BAS or reviewing your numbers, this tool gives you a clearer view of your actual business performance.
GST + Profit Estimator
Enter your revenue and expenses, choose whether the figures already include GST, then calculate your estimated position.
Results
What this calculator helps with
This tool is useful when you want a quick estimate before looking deeper into your BAS, bookkeeping, or cash flow.
- Estimate the GST portion in your revenue and expenses
- See whether your numbers suggest GST payable or refundable
- Work out profit on an ex-GST basis for cleaner decision-making
- Get a faster sense of how sales and costs are affecting your margin
How GST and profit work
For most Australian small businesses, GST is charged at 10% on taxable sales. If your business is GST registered, the GST you collect from customers is usually not part of your true revenue. In the same way, the GST included in business purchases is usually not part of your true operating expense when you can claim the input tax credit.
That is why it often makes more sense to assess profit on an ex-GST basis. It gives you a cleaner view of how the business is actually performing rather than mixing tax collections in with trading results.
How to use this calculator
- Enter your total revenue for the period.
- Enter your total business expenses for the same period.
- Select whether those figures already include GST.
- Click calculate to view the estimated GST and profit figures.
You can use it for a rough month, quarter, or custom period estimate. Just make sure revenue and expenses cover the same time frame.
Common GST and profit mistakes
- Using GST-inclusive sales as if they are true revenue
- Ignoring GST credits in supplier expenses
- Thinking profit automatically equals cash available
- Leaving BAS too late and getting surprised by a GST bill
- Mixing personal and business spending in the same numbers
Need more than a calculator?
If you want help keeping your numbers accurate and easier to manage, you can also look at our related services:
Frequently asked questions
What is GST in Australia?
GST stands for Goods and Services Tax. In Australia, the standard GST rate is 10% on most taxable goods and services.
Should profit be calculated including or excluding GST?
For GST-registered businesses, profit is usually better assessed excluding GST because GST collected is not generally business income and GST on claimable expenses is not usually a true business cost.
Can this calculator replace accounting advice?
No. It is a general estimator only. It does not cover GST-free sales, input-taxed items, partial credits, payroll, or business-specific tax treatment.
Who is this calculator for?
It is useful for Australian small business owners who want a quick estimate before reviewing BAS, bookkeeping, or profit numbers in more detail.
How do I calculate GST in Australia?
GST is typically calculated at 10% on taxable sales. If your figures include GST, divide by 1.1 to find the GST-exclusive amount. If they exclude GST, multiply by 10% to calculate the GST portion.