Enter amount and GST rate, select calculation type, then click "Calculate GST".
Example: $100 + 18% GST = $118 total, or $118 inclusive → $100 base + $18 GST
The GST Calculator helps you compute the Goods and Services Tax (GST) on any product or service. Whether you need to add GST to a net price (exclusive) or extract GST from a gross price (inclusive), this GST tax calculator provides instant results. It supports any currency and any GST rate, making it perfect for businesses, accountants, and consumers worldwide.
GST Formulas
GST (exclusive) = Amount × (Rate / 100)
Total (exclusive) = Amount + GST
Original (inclusive) = Total / (1 + Rate/100)
GST (inclusive) = Total − Original
For example, if you have a product priced at $100 excluding 18% GST, the GST amount is $18 and the total is $118. If you have a total of $118 that already includes 18% GST, the original amount is $100 and the GST is $18. Our calculator handles both scenarios.
Applications
Business invoicing: Calculate GST to charge customers correctly.
Tax filing: Determine GST payable or input tax credit.
Price comparison: Compare pre‑tax prices across different GST rates.
Budgeting: Understand how much tax you actually pay on purchases.
Understanding GST Exclusive vs. Inclusive
Exclusive GST: Used when the quoted price does not include tax. Common in B2B transactions and wholesale pricing. You add GST on top.
Inclusive GST: Used when the quoted price already includes tax. Common in retail and consumer pricing. You extract the GST component from the total.
GST Exclusive Tax Breakdown Reference Table
Base Net Amount
5% GST
12% GST
18% GST
28% GST
$100 Net Price
$105.00 ($5.00 GST)
$112.00 ($12.00 GST)
$118.00 ($18.00 GST)
$128.00 ($28.00 GST)
$500 Net Price
$525.00 ($25.00 GST)
$560.00 ($60.00 GST)
$590.00 ($90.00 GST)
$640.00 ($140.00 GST)
$1,000 Net Price
$1,050.00 ($50.00 GST)
$1,120.00 ($120.00 GST)
$1,180.00 ($180.00 GST)
$1,280.00 ($280.00 GST)
$5,000 Net Price
$5,250.00 ($250.00 GST)
$5,600.00 ($600.00 GST)
$5,900.00 ($900.00 GST)
$6,400.00 ($1,400.00 GST)
GST Rates Around the World
India: 5%, 12%, 18%, 28% (plus cess on luxury goods)
Australia: 10% GST
Canada: 5% GST (plus provincial sales taxes)
United Kingdom: 20% VAT (similar to GST)
Singapore: 8% GST (rising to 9% in 2024)
Malaysia: 6% SST (replaced GST)
New Zealand: 15% GST
How to Calculate GST Backwards (Reverse Charge)
If you know the total amount including GST and want to find the original price and the GST amount, divide the total by (1 + GST rate/100). For example, a ₹118 total with 18% GST: ₹118 / 1.18 = ₹100 (original). Then subtract: ₹118 − ₹100 = ₹18 GST. This is useful for claiming input tax credit or understanding actual costs.
Common Mistakes When Calculating GST
Using the wrong rate: Different products have different GST rates (e.g., essential vs. luxury).
Confusing exclusive vs. inclusive: Adding GST to an already inclusive price double‑counts tax.
Rounding errors: Always use at least two decimal places for accurate tax filing.
Forgetting to add GST on shipping/charges: Delivery fees are often taxable.
Input Tax Credit (ITC) – How Businesses Benefit
Businesses registered for GST can claim credit for the GST they pay on purchases (inputs). This reduces the net GST payable. For example, if you collect $100 GST from customers but paid $40 GST on supplies, you only remit $60 to the government. Our calculator helps compute GST on both sales and purchases for ITC calculation.
Use this GST calculator for all your tax calculations. Bookmark it to quickly determine GST amounts for invoices, purchase orders, or personal budgeting. Whether you are a business owner, accountant, or consumer, this tool simplifies GST computation.
GST is a comprehensive destination-based indirect tax levied on the manufacture, sale, and consumption of goods and services at the national level.
What is the difference between GST Inclusive and GST Exclusive?
GST Exclusive means tax is added to the base net price. GST Inclusive means the gross price already contains the tax, which is extracted backwards.
How do I calculate GST backwards (Reverse GST)?
To remove GST from a total price: Net Price = Gross Total / (1 + GST Rate / 100). The GST Tax Amount = Gross Total − Net Price.
What are the common GST tax slabs in India?
India operates a 4-tier GST slab structure: 5% (essential goods), 12% (standard goods), 18% (services & industrial items), and 28% (demerit & luxury goods).
How does Input Tax Credit (ITC) work?
Input Tax Credit allows businesses to deduct the GST they paid on purchases (inputs) from the GST they collect on sales (outputs) when remitting tax to the government.
What is CGST, SGST, and IGST?
In dual-GST systems like India, CGST (Central GST) and SGST (State GST) apply to intra-state sales (split 50/50), whereas IGST (Integrated GST) applies to inter-state transactions.
Can consumers claim GST refunds?
Generally, end consumers cannot claim GST refunds unless they qualify under specific tourist tax-refund schemes or export tax exemption rules.
Does this calculator work for UK VAT, Australian GST, and Canadian GST?
Yes! Because the percentage mathematics for VAT and GST are identical worldwide, simply input your country's tax percentage rate.