How to use GST Calculator
Calculate a tax-exclusive total or separate the base amount and tax from a GST-inclusive price using the rate you enter.
- Enter the amount and the applicable GST percentage.
- Choose Add GST for a price before tax, or Remove included GST for a final price that already includes tax.
- Calculate and read the base, tax, and total amounts together.
Worked example
At an illustrative 18% rate, ₹1,000 before tax produces ₹180 GST and a ₹1,180 total. Removing included GST from ₹1,180 at the same rate gives a ₹1,000 base and ₹180 tax.
Limits and things to check
The rate must be between 0% and 100%. This tool does not select the legally applicable rate, split CGST/SGST, or account for cess and invoice-specific rounding. Check the applicable rate independently.
Why not subtract 18% from a tax-inclusive price?
The percentage applies to the base, not the total. Base = total ÷ (1 + rate/100); tax = total − base. Adding tax uses tax = base × rate/100.
Processing and privacy
Your browser performs the operation locally. Inputs and results are not sent to OneClickWorks.
Common questions
Does this tool upload my input?
No. Processing happens in this browser tab and your input is not sent to OneClickWorks.
What happens when I leave the page?
In-memory input and generated download links are released when the page is reset, replaced, or closed. OneClickWorks does not persist tool content.