GST Calculator

Calculate the GST amount on a base price and see the total after applying the entered rate. The calculator performs arithmetic only; it does not decide which GST rate applies to a transaction.

Calculator

GST Amount—

Base Amount—

Total—

Important: The calculator performs a mathematical percentage calculation. Applicable GST rates, exemptions and transaction rules must be verified separately.

What is the GST Calculator?

GST treatment depends on the supply, classification, place of supply and applicable rules. The rate entered by the user should be verified before using the result for invoicing.

How the calculation works

GST amount = base amount × GST rate ÷ 100. Total including GST = base amount + GST amount. For an inclusive price, a different reverse-calculation formula is required.

Worked example

For a base amount of ₹10,000 and an entered GST rate of 18%, the GST amount is ₹1,800 and the total is ₹11,800.

How to use this calculator

Enter the values that apply to your situation.
Check the rate, period and other assumptions before calculating.
Click Calculate and review each part of the result, not only the headline number.
Change one input at a time if you want to compare different scenarios.

How to interpret the result

GST treatment depends on the supply, classification, place of supply and applicable rules. The rate entered by the user should be verified before using the result for invoicing. Use the result as a planning estimate and compare it with the terms, rates or rules that actually apply to you.

Practical tips

Confirm the correct GST rate for the product or service.
Distinguish between GST-inclusive and GST-exclusive prices.
Keep tax invoices and transaction records where required.
Check current GST rules and notifications for unusual transactions.

Important limitations

The calculator does not determine tax classification or eligibility.
It does not calculate every GST component or compliance requirement.
Rates and exemptions can change.

Frequently Asked Questions

What is GST?

GST is an indirect tax applied to eligible supplies under India's GST framework.

Does this calculator determine the correct GST rate?

No.

Can it calculate an inclusive GST price?

This page focuses on adding the entered rate to a base amount.

Is it an official GST calculator?

No.

Last reviewed: August 2026. Rate-sensitive rules and institutional terms can change; verify current information before making an important decision.