GST Calculator
Add or remove GST from any amount and see the CGST, SGST and IGST breakdown across every Indian GST slab.
About this calculator
The Goods and Services Tax (GST) is an indirect tax applied to most goods and services in India. This free GST calculator lets you add GST to a base price or remove it from a GST-inclusive total, and it instantly shows the GST amount along with the CGST, SGST, and IGST breakdown. It supports every standard slab — 3%, 5%, 12%, 18%, and 28% — plus any custom rate you type.
Use it to price products, raise invoices, verify a bill, or work out how much tax is hidden inside an inclusive price. For intra-state transactions GST is split equally into CGST and SGST; for inter-state transactions the full amount is IGST. All calculations run locally in your browser with no data uploaded. Results are estimates for planning — confirm the exact applicable rate and any cess with a qualified accountant.
Why use this tool
Add or remove GST
Calculate GST-inclusive and GST-exclusive prices both ways.
All slabs
Works with 5%, 12%, 18% and 28% or any custom rate.
Instant split
See the base amount, GST amount and final total clearly.
Common use cases
- Work out the GST on an invoice
- Find the pre-tax price from a final amount
- Check the tax on a purchase
- Prepare quotes with correct GST
Frequently asked questions
Enter the original price and choose a GST rate. GST amount = price × rate ÷ 100, and the total = price + GST. For example, ₹1,000 at 18% adds ₹180 for a total of ₹1,180.
Switch to “Remove GST” and enter the GST-inclusive total. Original price = total ÷ (1 + rate ÷ 100), and the GST is the difference. This is how you back out the tax from an inclusive price.
For sales within a state, GST splits equally into CGST (central) and SGST (state) — each half of the total GST. For inter-state sales, the full amount is charged as IGST.
Indian GST slabs are 3%, 5%, 12%, 18%, and 28% depending on the goods or service. Pick the relevant preset or type a custom rate.
The arithmetic is exact. However, specific items may attract a cess or fall under a special rate, so confirm the applicable rate for your product with a tax professional.