How to use the GST Calculator
Fill in the fields on the left. Results, charts and the breakdown update instantly as you type or move a slider. Pick your country at the top of the page to switch currency.
Formula
Add GST: total = amount × (1 + rate)
Remove GST: base = amount ÷ (1 + rate)
CGST = SGST = GST ÷ 2
Frequently asked questions
What are the GST rates?
After the GST 2.0 reform of September 2025, the main slabs are 5% and 18%, with 40% on luxury and sin goods. 0%, 0.25% and 3% apply to specific items.
Results are estimates for information only and are not financial, tax or legal advice. Tax rules, interest rates and fees change, so confirm important numbers with your bank, employer or a qualified adviser. Read our disclaimer.