How to remove GST from a price
- Type the total price that includes GST.
- Pick the GST rate, or type your own.
- Read the price before GST and the tax split.
Examples
A bill of ₹1,180 at 18% GST: the price before GST is ₹1,000 and the GST is ₹180, which is ₹90 CGST and ₹90 SGST.
A total of ₹525 at 5%: the price before GST is ₹500 and the GST is ₹25.
A total of ₹10,000 at 18%: 10,000 x 100 / 118 gives ₹8,474.58 before GST, so the GST is ₹1,525.42, or ₹762.71 each of CGST and SGST.
A total of ₹1,40,000 at the 40% rate: the price before GST is ₹1,00,000 and the GST is ₹40,000, all IGST if the sale is to another state.
About this tool
A reverse GST sum starts from the amount you paid and works back to the price before tax. This page opens in that mode. Type the total, choose the rate, and read the price before GST, the GST inside it, and the CGST and SGST halves for a sale within one state, or IGST for a sale to another state.
Common questions
What is the reverse GST formula?
Price before GST = total x 100 / (100 + rate). The GST is the total minus that price. At 18%, 1,180 x 100 / 118 = 1,000, so the GST is 180.
Why can't I take 18% off the total?
The 18% was worked out on the lower price, not on the total. 18% of 1,180 is 212.40, which is more than the 180 of GST inside it.
When is it CGST and SGST, and when IGST?
For a sale within one state the GST is split equally into CGST and SGST. For a sale to another state the whole amount is IGST.
Is it free to use?
Yes. There's no sign-up, and you can use it as often as you like.
Is my text uploaded anywhere?
No. This tool runs inside your browser, so what you enter stays on your device.
Do I need to install anything?
No. It works in your browser on a computer or a phone.