GST Calculator — Add or Remove GST From Any Amount
Quickly calculate the GST amount on a price, or work out the original price before GST was added.
Goods and Services Tax (GST) calculations are a routine part of invoicing, pricing, and bookkeeping. Whether you need to add GST to a base price or extract the GST component from a GST-inclusive price, doing it manually for different tax rates (5%, 12%, 18%, 28%, etc.) is tedious and error-prone.
Our GST Calculator handles both directions: calculate the GST amount and total price when adding GST to a base price, or calculate the base price and GST amount when working backward from a GST-inclusive total.
🛠 Ready to try it? Use the GST Calculator now — free, no signup required.
Open GST Calculator →How to Use the GST Calculator
- Open the GST Calculator tool.
- Enter the amount.
- Select the applicable GST rate (e.g., 5%, 12%, 18%, 28%, or a custom rate).
- Choose whether the entered amount excludes GST (add GST) or includes GST (extract GST).
- View the calculated GST amount and total/base price.
Common Use Cases
- Calculating the GST amount to add to an invoice for goods or services.
- Working out the original (pre-GST) price from a GST-inclusive amount shown on a receipt.
- Comparing total costs across different GST rate categories.
- Quickly checking GST calculations on a quotation or purchase order.
- Learning how GST-inclusive and GST-exclusive pricing differ.
Frequently Asked Questions
How is GST calculated when adding to a price?
GST amount = base price × (GST rate / 100). The total price is the base price plus the GST amount — for example, ₹1,000 with 18% GST adds ₹180, for a total of ₹1,180.
How do I find the GST amount from a GST-inclusive price?
Base price = GST-inclusive price / (1 + GST rate/100), and GST amount = GST-inclusive price - base price — for example, ₹1,180 at 18% GST has a base price of ₹1,000 and GST of ₹180.
What are the common GST rate slabs in India?
Common GST rates include 0%, 5%, 12%, 18%, and 28%, depending on the category of goods or services — always confirm the applicable rate for your specific product or service.
Is this calculator suitable for filing official tax returns?
This tool is intended for quick estimates and general calculations. For official tax filings and compliance, consult a qualified tax professional or your accounting software, as rates and rules can vary and change.
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