GST Calculator
Calculate Goods and Services Tax on any amount. See the CGST, SGST and IGST breakdown and the total payable including GST.
How GST is calculated
Goods and Services Tax (GST) is calculated as a percentage of the base amount. The formula is GST = (Amount × Rate) ÷ 100. For intra-state (within the same state) supplies, the GST is split equally between CGST (Central GST) and SGST (State GST). For inter-state supplies, the entire tax is charged as IGST (Integrated GST).
For example, on a ₹10,000 invoice at 18% GST, the total GST is ₹1,800 — split into ₹900 CGST and ₹900 SGST for an intra-state sale, or charged as ₹1,800 IGST for an inter-state sale. The total payable is ₹11,800.
Common GST rates
- 0% — Essential unbranded goods and services
- 5% — Essential commodities, packaged food
- 12% — Processed food, certain goods
- 18% — Most goods and services (default rate)
- 28% — Luxury items, automobiles, tobacco
What Does a GST Calculator Do?
A GST calculator works out the tax on a price, or the total once GST is added. It saves time on quotations, invoices, estimates, or just checking a number by hand.
The actual GST rate depends on your country and the transaction, so use whatever rate applies to your situation.
What Goes Into a GST Calculation
- Base amount: The price before GST, if that's where you're starting.
- GST rate: The tax percentage that applies.
- Tax amount: The GST portion, worked out from the taxable amount.
- Gross amount: The final total once GST is added.
- Inclusive calculations: If the price already includes GST, you can separate the tax out.
- Rounding: Check final figures match the rounding your business or local rules use.
How to Use It
- Open the GST Calculator.
- Enter the amount and the GST percentage for your transaction.
- Pick the calculation direction if there's an option.
- Check the tax amount and total.
- Use the verified number in your document.
Frequently Asked Questions (FAQs)
1. What does a GST calculator do?
It calculates the GST amount and total based on what you enter.
2. Can I work out GST already included in a price?
Yes, if there's an inclusive-tax option — it'll pull the GST portion out.
3. Does the calculator know my local GST rate?
No — use whatever rate applies to your transaction; rates aren't universal.
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