GST Calculator

Enter an amount and a GST rate. Add GST to a net price or separate it from a total that already includes tax.

Use the calculator when you have already determined the rate that applies to the transaction. The same math powers the VAT workspace.

  • 100% free
  • No registration
  • On your device
  • Modern browser
  1. 1Enter details
  2. 2View result
$1000.00Net Amount
$180.00Tax Amount
$1180.00Total Amount

Your input stays on this device for this operation. We don’t upload or store it.

About GST Calculator

Use the calculator when you have already determined the rate that applies to the transaction. The same math powers the VAT workspace.

Exclusive calculation

Tax is net amount multiplied by the rate as a decimal.

Inclusive calculation

Net amount is gross divided by one plus the decimal rate.

How to use GST Calculator

  1. 1

    Enter the amount

    Choose a nonnegative net or gross price.

  2. 2

    Enter the rate

    Replace the default with your applicable percentage.

  3. 3

    Select tax mode

    Use Add Tax for net input or Remove Tax for gross input.

Formats and practical limits

Amount, user-supplied percentage and mode → net, tax and total

  • It does not select a jurisdiction, tax category or local rate.
  • It does not split components such as CGST and SGST or prepare invoices.

Practical example

At a hypothetical 10%, adding tax to 200 gives tax of 20 and total of 220.

Further reading

Frequently Asked Questions

1 answers
Is the prefilled rate an official rate?

Treat it as a sample. Use the rate applicable to your transaction.