Free Online Calculators
Add or remove GST for India, Australia, New Zealand, Canada and Singapore
Add GST: amount × (1 + rate ÷ 100), so ₹10,000 at 18% becomes ₹11,800. Remove GST: total ÷ (1 + rate ÷ 100), so ₹11,800 contains ₹1,800 of GST. Within a state, 18% GST splits into 9% CGST and 9% SGST. Also covers Australia, New Zealand, Canada and Singapore.
At 18% GST, ₹1,000 plus GST is ₹1,180.00 (₹180.00 of GST), and a price of ₹1,000 including GST contains ₹152.54 of GST. Within a state, 18% splits into 9% CGST and 9% SGST. Add GST: amount × (1 + rate ÷ 100). Remove GST: total ÷ (1 + rate ÷ 100).
| GST rate | GST on 1,000 | Total with GST | GST included in 1,000 |
|---|---|---|---|
| 5 % | 50.00 | 1,050.00 | 47.62 |
| 9 % | 90.00 | 1,090.00 | 82.57 |
| 10 % | 100.00 | 1,100.00 | 90.91 |
| 13 % | 130.00 | 1,130.00 | 115.04 |
| 14 % | 140.00 | 1,140.00 | 122.81 |
| 15 % | 150.00 | 1,150.00 | 130.43 |
| 18 % | 180.00 | 1,180.00 | 152.54 |
| 40 % | 400.00 | 1,400.00 | 285.71 |
Multiply the amount before tax by the GST rate and divide by 100. At 18%, GST on ₹10,000 is ₹1,800, and the total is ₹11,800.
Divide the total by (1 + rate ÷ 100). At 18%, ₹11,800 ÷ 1.18 = ₹10,000, so the total includes ₹1,800 of GST.
Since 22 September 2025 the main GST rates are 5% and 18%, with 40% for luxury and demerit goods and 0% for exempt items. The earlier 12% and 28% slabs have largely been removed.
For sales within a state, GST is split equally into CGST for the centre and SGST for the state. For sales between states the full amount is charged as IGST. The total tax is the same.
Australia charges 10% GST. To add it, multiply by 1.1; to find the GST included in a price, divide the price by 11. A $110 price includes $10 of GST.
To add GST to a price, multiply the amount before tax by the GST rate. GST = amount × rate ÷ 100, and the total = amount × (1 + rate ÷ 100). At 18%, ₹10,000 plus GST is ₹10,000 + ₹1,800 = ₹11,800.
If a price already includes GST, divide it by (1 + rate ÷ 100) to get the amount before tax. At 18%, ₹11,800 ÷ 1.18 = ₹10,000, so the GST included is ₹1,800. Do not simply take 18% of the total: 18% of ₹11,800 would be ₹2,124, which is too much. In Australia, with 10% GST, the GST included in a price is one eleventh of it: $110 contains $10 of GST.
Since 22 September 2025, India applies GST in the main slabs of 5% and 18%, with 40% for luxury and demerit goods and 0% for exempt essentials. The earlier 12% and 28% slabs have largely been removed; the calculator still offers them for older invoices. The rate depends on the HSN or SAC code of the goods or service, so check the applicable rate before invoicing.
For a sale within the same state, GST is split equally into central GST (CGST) and state GST (SGST): 18% GST becomes 9% CGST plus 9% SGST. For a sale between states, the whole amount is integrated GST (IGST). The total tax is the same in both cases. Choose the supply type in the calculator to see the split.
Rates were checked in September 2026. Tax rates change, so confirm them with the tax authority when the amount matters.