Quick examples
Base Amount
$10,000
GST Amount
$1,800
Total Amount
$11,800
GST Calculator — Quick Reference
The GST Calculator is an online tool that calculate GST amount on goods and services — add GST to base price or extract from inclusive price. Everything for the GST Calculator is on this page: the interactive calculator, the formula, a worked example, step-by-step guidance, and frequently asked questions — no other pages required.
At a glance
- Main inputs
- Income or transaction amount
- Deductions and tax rate or slab
- Main outputs
- Tax payable
- Net amount after tax
Direct answers
What is the GST Calculator?
The GST Calculator is an online tool that calculate GST amount on goods and services — add GST to base price or extract from inclusive price.
What formula does the GST Calculator use?
This calculator uses the rule: GST = Taxable Amount × Rate / 100. Enter your values in the tool above to apply it to your numbers.
How does the GST Calculator work?
Select exclusive (tax added on top) or inclusive (tax included in price) mode, enter amount and GST rate to get base amount, GST, and total.
Formula Used
The equation below is what this calculator applies. Variable definitions follow when symbols are used.
Equation
GST = Taxable Amount × Rate / 100
Worked Example: $10,000 + 18% GST
Sample inputs and the results this calculator produces for the scenario below.
Inputs
- Base Amount
- $10,000
- GST Rate
- 18%
Results
- GST Amount
- $1,800
- Total (inclusive)
- $11,800
Common GST slabs are 5%, 12%, 18%, and 28%. Use exclusive mode to add GST or inclusive mode to back out tax from a gross price.
How GST Calculator Works
Select exclusive (tax added on top) or inclusive (tax included in price) mode, enter amount and GST rate to get base amount, GST, and total.
What to enter
Use the calculator above to set your amounts, rates, and tenure. Results update as you move sliders or type values — switch currency if you are planning in USD, INR, or another supported unit.
Step-by-step
- Open the GST Calculator and enter your amounts, rates, and time period in the input fields.
- Review the results panel — totals update instantly when you change any value.
- Compare the worked example and formula below to verify the math matches your scenario.
- Read the FAQs for common edge cases, tax notes, and planning tips specific to this calculator.
GST — Frequently Asked Questions
Each question is answered directly below. Expand any item for the full response.
How do you calculate GST on a price?
For an exclusive price, GST amount = taxable value x GST rate and invoice total = taxable value + GST. For an inclusive price, GST is backed out by multiplying the inclusive amount by rate / (100 + rate).
What is the difference between CGST, SGST, and IGST?
In an intra-state supply, GST is usually split equally into CGST and SGST. In an inter-state supply, IGST typically applies instead of the split.
Why is input tax credit important in GST planning?
Input tax credit reduces the effective tax cost for eligible registered businesses because tax paid on inputs can offset tax collected on outputs. Cash flow planning becomes much easier when you know whether credit is available or blocked.
What is a common GST calculator mistake?
Users often apply GST on a price that already includes GST, or they use the wrong slab for the supply. Checking whether the amount is inclusive or exclusive is just as important as knowing the rate.
Disclaimer
- This calculator gives you an estimate only. It is not a promise of exact results.
- This is general information, not personal financial, tax, or legal advice.
- You are responsible for your own decisions. Talk to a qualified professional when it matters.
- Tax laws change and depend on your income, country, and personal situation.