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GST Calculator
GST Calculator
Quickly calculate inclusive or exclusive GST amounts
$0
Total with GST
GST Amount
$0
Net Amount
$0
Tax Breakdown
About the GST Calculator
Calculate GST for a price, either by adding it to a GST-exclusive amount or by finding the amount before GST from a GST-inclusive total.
How to use the GST Calculator
- Enter the Amount ($) and the GST Rate (%).
- Choose the Calculation Type: GST Exclusive (add GST) or GST Inclusive (find the amount before GST).
- Press Calculate GST.
Formula and method
Exclusive: GST = Amount × Rate ÷ 100 and Total = Amount + GST.
Inclusive: GST = Total − Total ÷ (1 + Rate ÷ 100).
Worked example
Adding 10% GST to $200 gives $20 GST and a total of $220. For a $220 inclusive price, the GST portion is $220 − ($220 ÷ 1.10) = $20.
Adding GST. With an 18% rate, 1,000 attracts 180 of GST, so the total is 1,180. To remove GST from 1,180, divide by 1.18 to get 1,000.
When to use the GST Calculator
- Adding GST to a price for an invoice or a quote.
- Removing GST from a GST-inclusive amount.
- Checking the GST portion of a bill before you pay.
Common mistakes to avoid
- Using the wrong slab. GST rates are set by category, so check the rate that applies to your goods or services.
- Applying GST twice to a price that already includes it.
- Confusing the GST-exclusive price with the amount you actually pay.
Tips
- GST rates and rules differ by country and by item, so check your local tax authority.
- Keep tax invoices if you are registered and want to claim input credits.
Frequently Asked Questions
Exclusive means the tax is added on top of the price. Inclusive means the tax is already inside the price shown.
Divide the total by 1 plus the rate to get the base price, then subtract it from the total.
A registered business can usually deduct the GST it paid on purchases from the GST it collects on sales.
No. Countries that use GST set their own rates and rules, so use the local rate.