Enter values and select Calculate to see your result.
Add or Remove Tax
Use a custom tax percentage to calculate tax-inclusive or tax-exclusive amounts.
View formula
Tax = Net amount × Tax rate
How to use the GST / VAT Calculator
Add GST or VAT to a net amount or remove included tax from a gross total.
- Enter amount and tax rate.
- Choose add or remove included tax.
- Calculate tax and resulting amount.
GST / VAT Calculator formula
Tax added = net × rate; tax removed = gross × rate ÷ (100 + rate).
Worked example
Inputs: $100 at an 18% GST/VAT rate using Add tax.
What to expect: Tax is $18 and tax-inclusive amount is $118.
How to read your result
Use the jurisdiction's rate; exemptions and rounding vary by product.
Frequently asked questions
Can I remove included VAT?
Yes. Choose Remove included tax and enter the gross total.
Does it know country rules?
No. It applies the rate and mode provided.