GST Calculator
Add or remove GST from any amount with real-time calculations. Supports multiple countries, India's GST slabs, and custom rates.
Calculation Settings
Calculation Results
Enter an amount to see results
About GST Calculator
The GST Calculator is a free online tool for adding or removing Goods and Services Tax from any amount. Whether you need the GST-inclusive total from a net figure or want to extract the tax component from a gross price, the tool handles both directions with the mathematically correct formula. It covers seven countries and regions — India, Australia, New Zealand, Canada (HST/GST), Singapore, the United Kingdom (VAT), and Germany (VAT) — each pre-loaded with its standard rate and the correct currency symbol so you see figures in context.
For Indian users the calculator includes all five GST rate slabs — 0%, 5%, 12%, 18%, and 28% — as one-click preset buttons, which matches the tiered structure of India's GST regime. You can also type any custom rate if your goods or services fall under a special rate or if you are working with a jurisdiction not in the country list. Results appear instantly as you type: the panel on the right shows the amount excluding GST, the GST portion highlighted in red, and the total including GST highlighted in green, plus a detailed calculation breakdown table that you can copy to your clipboard in one click.
All calculations run entirely in your browser using JavaScript arithmetic. No amount, rate, or country selection is sent to a server or logged anywhere. The tool works offline once the page has loaded, making it safe for confidential invoices and internal financial estimates. There is no registration, no usage limit, and no cost.
Key Features
Add and remove GST in both directions
Switch between "Add GST" (net to gross) and "Remove GST" (gross to net) with a single click. The remove formula uses base = gross / (1 + rate/100), which is the correct reverse calculation — not just subtracting the percentage from the total.
India GST slab presets
One-click buttons for 0%, 5%, 12%, 18%, and 28% map directly to India's five GST rate slabs, so you do not need to look up or type the rate for standard goods and services categories.
Seven-country coverage with auto rate and currency
Select India, Australia, New Zealand, Canada, Singapore, the UK, or Germany and the correct standard rate and currency symbol load automatically, giving results in ₹, A$, NZ$, C$, S$, £, or €.
Custom rate for any jurisdiction
Type any decimal rate — such as 6.5% for a state-level sales tax or 7.7% for Swiss VAT — and the calculator applies it immediately without requiring a country selection.
Real-time three-part breakdown
As you type, the results panel updates instantly with three separate figures: amount excluding GST, GST amount, and total including GST, colour-coded and displayed in a summary table.
Copy results to clipboard
One button copies the three-line breakdown — base, GST, total — as formatted text, ready to paste into an invoice, spreadsheet, or chat message.
How to Use
Choose Calculation Type
Select Add GST to calculate the total from a net amount, or Remove GST to extract GST from a gross amount.
Enter Amount
Type the amount you want to calculate. Results update instantly as you type.
Set GST Rate
Click a preset rate button (0%, 5%, 12%, 18%, 28%) or enter a custom rate. Choose a country to load its standard rate.
View Results
See the amount excluding GST, GST amount, total including GST, and a calculation breakdown on the right.
Example
A freelancer invoices a client ₹50,000 for a consulting project in India. With GST at 18%, the tool calculates the tax due and the total amount to charge.
Calculation type: Add GST
Amount (excluding GST): ₹50,000.00
GST rate: 18% (India — standard rate)Amount (Excl. GST): ₹50,000.00
GST (18%): ₹9,000.00
Total (Incl. GST): ₹59,000.00Common Use Cases
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Raising invoices with correct GST
Freelancers and small businesses registered under GST need to show the tax amount separately on every invoice. Enter the net service fee, select the applicable slab (typically 18% for professional services), and copy the three-line breakdown directly into your invoice template.
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Checking whether a quoted price includes GST
Suppliers in India often quote prices that may or may not include GST. Use the Remove GST direction to find the net amount hidden inside a gross figure — useful before comparing quotes that are stated differently.
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Reconciling GST on imported goods in Australia or New Zealand
Australia levies 10% GST and New Zealand 15% on most imported goods above a de minimis threshold. Select the relevant country, enter the landed cost, and instantly see how much of the total is GST for customs or accounting records.
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Estimating retail prices for e-commerce listings
Online sellers need to display GST-inclusive prices to consumers. Enter your base cost plus margin, add the correct slab rate, and see the final retail price before publishing the listing.
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Cross-checking line items on tax invoices
When auditing a supplier invoice, enter each gross line amount with the stated rate to verify the GST component independently — without relying on the supplier's arithmetic.