Finance
Add or remove GST from any amount, at any standard rate — instant result as you type.
Total (incl. GST)
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GST is calculated as a straightforward percentage of the base amount when adding it, but removing GST from a tax-inclusive total requires dividing by (1 + rate/100) rather than simply subtracting the percentage — a distinction this calculator's two modes handle correctly for you.
A product priced at ₹1,000 before tax, with 18% GST added, comes to ₹1,180 total — ₹180 in GST. Working backward from a ₹1,180 tax-inclusive price to find the pre-tax base isn't simply subtracting 18%; dividing by 1.18 gives the correct base of ₹1,000, which is exactly what the "Remove GST" mode does automatically.
A common mistake is assuming that removing 18% GST from a ₹1,180 total means subtracting 18% of ₹1,180 (₹212.40), landing on the wrong base amount. Because the original 18% was added to a smaller base, working backward requires dividing by 1.18, not subtracting 18% of the total — a distinction that trips up manual calculations regularly.
Multiply the amount by the GST rate divided by 100 to get the tax, then add it to the original amount. For example, ₹1,000 at 18% GST adds ₹180, for a total of ₹1,180. Use the "Add GST" tab above.
Divide the total by (1 + rate/100) to get the base amount, then subtract that from the total to find the GST portion. Use the "Remove GST" tab — useful when a price already includes tax and you need to know the pre-tax value.
India's GST system uses four main slabs — 5%, 12%, 18%, and 28% — depending on the category of goods or services. This calculator includes all four as quick-select options.