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GST Calculator

Calculate GST on an original amount or separate tax from a GST-inclusive price.

Add GST to an amount

Calculate GST from an inclusive amount

About GST calculations

GST is calculated as a percentage of the taxable amount. To add GST, multiply the original amount by the tax rate and add the tax to the original amount. For an inclusive price, divide the total by one plus the tax rate to find the original amount.

Example: Adding GST to an Amount

Suppose the original taxable amount is ₹1,000 and, for this example, the GST rate entered is 18%.

Step 1: Calculate the GST amount.

GST = ₹1,000 × 18 ÷ 100 = ₹180.

Step 2: Add GST to the original amount.

Total price = ₹1,000 + ₹180 = ₹1,180.

The total in this illustrative example is ₹1,180, including ₹180 GST. This example explains the calculation only; it does not determine which GST rate applies to a real product or service.

Example: Finding GST in an Inclusive Price

Suppose a price already includes GST and the total is ₹1,180. If the GST rate used for this example is 18%, the original taxable amount can be calculated by dividing the total by 1.18.

Original amount: ₹1,180 ÷ 1.18 = ₹1,000.

GST amount: ₹1,180 − ₹1,000 = ₹180.

Therefore, in this example, the inclusive price of ₹1,180 contains an original amount of ₹1,000 and GST of ₹180.

Formulas Used

Tax rules and applicable rates can vary by product, service and transaction. Confirm the applicable rate before using these calculations for tax or accounting decisions.

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