GST Calculator
GST (Goods and Services Tax) is a consumption tax added to the price of most goods and services. This calculator works both ways: add GST to a net price to get the total, or remove GST from a gross price to see the tax and the pre-tax value.
Net amount when adding GST, or gross amount when removing it.
Within one state the tax splits into CGST and SGST; across states it is a single IGST.
Add GST to a net price, or extract GST from a gross price.
How to calculate GST
To add GST, the amount is multiplied by the rate and the result is added to the price. To remove GST, the gross amount is divided by one plus the rate to recover the net price, and the difference is the GST. Use the toggle to switch modes.
Add: GST = Amount × Rate. Remove: Net = Gross ÷ (1 + Rate).Example. On a net price of ₹1,000 at 18% GST, the GST is ₹180 and the gross total is ₹1,180. Removing 18% GST from ₹1,180 returns the ₹1,000 net price.
Adding vs removing GST
Add GST when you have a pre-tax price and need the final amount a customer pays. Remove GST when you have a tax-inclusive total, for example on a receipt, and need the tax component for input credits and bookkeeping.
CGST, SGST and IGST - what the split means
In India the same GST rate is collected in one of two ways. When buyer and seller are in the same state the tax divides equally into CGST, which goes to the central government, and SGST, which goes to the state - 18% becomes 9% CGST plus 9% SGST. When the supply crosses a state border it is instead charged as a single IGST at the full 18%, which the centre later apportions. The customer pays exactly the same total either way; the split only determines who receives it and how it appears on the invoice. Getting it wrong on a tax invoice is one of the most common GST filing errors, because the amount looks correct while the heads do not match the place of supply.
Common GST rates
Rates vary by country and product. India uses slabs of 0, 5, 12, 18 and 28 percent, plus a special 3 percent rate on gold and jewellery; 18 percent is the most common and covers most services. Australia and Singapore use a single rate, Canada layers GST with provincial taxes, and New Zealand uses 15 percent. Pick the rate that applies to your item.
Frequently asked questions
How do I add GST to a price?
Multiply the net price by the GST rate to get the GST amount, then add it to the net price. For 18% GST on 1,000, the GST is 180 and the total is 1,180.
How do I remove GST from a total?
Divide the gross amount by one plus the rate. For 18% GST, divide the total by 1.18 to get the net price, and the remainder is the GST.
What is the difference between CGST, SGST and IGST?
They are three collection heads for the same tax. Intra-state supply splits the rate evenly between CGST (central) and SGST (state), so 18% is 9% plus 9%. Inter-state supply is charged as one IGST at the full 18%. The total paid is identical; only the destination of the money and the invoice lines differ. Choose the supply type above to see your amount split correctly.
How do I calculate reverse GST from an invoice total?
Switch the toggle to Remove GST and enter the tax-inclusive total. The calculator divides by one plus the rate to recover the net value. For a 11,800 invoice at 18%, the net is 10,000 and the GST is 1,800 - which then splits into 900 CGST and 900 SGST for an intra-state sale.
Is GST the same as VAT?
They work the same way, as a consumption tax on the final price. Different countries use different names: GST in India, Australia and Canada, and VAT in the UK and much of Europe.
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