Question 1

How do I add GST to a net amount?

Accepted Answer

Multiply the net amount by (1 + GST rate). For example, with India's 18% GST: Gross = Net × 1.18. A net amount of 10,000 becomes 11,800 including GST.

Question 2

How do I remove GST from a gross amount?

Accepted Answer

Divide the gross (GST-inclusive) amount by (1 + GST rate). For example, with New Zealand's 15% GST: Net = Gross ÷ 1.15. A gross amount of 1,150 contains a net of 1,000 and GST of 150.

Question 3

What GST rates apply in different countries?

Accepted Answer

Common GST rates: India 18% (standard), New Zealand 15%, Australia 10%, Singapore 9%, Canada 5% (federal GST). This calculator works with any custom rate as well.