Free calculator
Reverse GST calculator
Have a price that already includes GST? Enter it with the rate to see the taxable value and how much of it is tax.
Within your state you charge CGST + SGST (half the rate each); to another state, IGST at the full rate.
GST breakdown
₹1,525.42
- Taxable value
- ₹8,474.58
- CGST @ 9%
- ₹762.71
- SGST @ 9%
- ₹762.71
- Total GST
- ₹1,525.42
- Amount (incl. GST)
- ₹10,000.00
How to remove GST from a price
Divide the GST-inclusive price by 1 plus the rate. For ₹11,800 at 18%: ₹11,800 ÷ 1.18 = ₹10,000 taxable value, so the GST inside it is ₹1,800.
A common mistake is to take 18% off the inclusive price. That gives ₹2,124, which is too much, because the 18% was charged on the lower, pre-tax amount.
The calculator keeps your total exactly as entered. It rounds the taxable value to the paisa, and the GST is whatever remains.
When you need it
- You quoted a customer an all-in price and now need the tax invoice to show the taxable value and GST.
- You are checking a supplier’s bill, or an expense receipt that shows only the total.
- You sell at round MRP-style prices and want to know your revenue before tax.
Last updated 2026-09-30. This calculator is a guide, not tax advice.
Frequently asked questions
What is the formula for reverse GST?
Taxable value = inclusive price × 100 ÷ (100 + GST rate). GST = inclusive price − taxable value.
How much GST is in ₹1,000 at 18%?
₹1,000 × 100 ÷ 118 = ₹847.46 taxable value, so the GST is ₹152.54: ₹76.27 CGST and ₹76.27 SGST within a state.
Should my invoice show the inclusive price or the taxable value?
A tax invoice shows the taxable value, the GST rate and the tax amounts separately, and then the total. Use the taxable value from this calculator as the item price.