GST / VAT Calculator

About the GST / VAT Calculator

The GST and VAT calculator handles the two most common tax operations needed by businesses, consumers, and accountants: adding a consumption tax to a price, and removing a consumption tax from a price that already includes it. These are called the exclusive and inclusive calculations respectively, and the difference between them is not merely the direction of arithmetic — it is a distinction that creates real financial errors when confused. If a product costs $90 before GST in Australia and you want to know the GST-inclusive price, you multiply by 1.10 to get $99. But if you have a GST-inclusive price of $99 and want to find the GST component, you do not multiply $99 by 10% (which gives $9.90, not the correct $9) — you divide by 11 (which gives exactly $9). This reversal catches out even experienced bookkeepers. Our calculator handles both modes across all major jurisdictions: Australia (10% GST), New Zealand (15% GST), Canada (5% federal GST, with provincial HST variants), the United Kingdom (20% VAT, with reduced 5% and zero rates for certain goods), and all European Union member states including Germany (19% MwSt), France (20% TVA), Ireland (23% VAT), Italy (22% IVA), Spain (21% IVA), Netherlands (21% BTW), and Sweden (25% Moms). Goods and Services Tax (GST) and Value Added Tax (VAT) are functionally the same mechanism with different names — a consumption tax collected at each stage of the supply chain, with businesses claiming back the tax they paid on inputs (input tax credits in Australia's BAS system, VAT returns in the UK) and remitting only the net tax on their value added. For consumers, only the final retail stage is visible: the total amount paid. For businesses, the process of tracking GST/VAT paid versus collected and lodging periodic returns to the relevant authority — ATO in Australia, HMRC in the UK, IRD in NZ — is a compliance requirement with specific deadlines and record-keeping obligations. The calculator also accommodates the US sales tax situation, where there is no federal GST or VAT and instead each state sets its own sales tax rate, with some counties and cities adding additional local taxes on top. US sales tax rates range from 0% in Alaska, Montana, New Hampshire, Oregon, and Delaware to a combined rate of over 10% in parts of Tennessee and Louisiana. For US users, the calculator provides a custom rate input. Whether you are a small business owner checking an invoice, an e-commerce seller calculating tax on international sales, a tourist seeking a VAT refund on purchases made in Europe, or an accountant reconciling a quarterly BAS return, this tool gives you the precise calculation instantly without the risk of arithmetic error or formula confusion.

How It Works

Two modes. Mode 1 — Adding tax (exclusive to inclusive): Final Price = Original Price × (1 + rate/100). Tax Amount = Original Price × (rate/100). Example: $150 + 10% Australian GST = $150 × 1.10 = $165. GST component = $15. Mode 2 — Removing tax (inclusive to exclusive): Original Price = Inclusive Price ÷ (1 + rate/100). Tax Amount = Inclusive Price − Original Price. Example: £240 UK price including 20% VAT. Original price = £240 ÷ 1.20 = £200. VAT component = £40. Note: the VAT component is NOT £240 × 20% = £48 — that is a common error. Always divide by (1 + rate) to extract the correct tax from an inclusive price.

Tips & Best Practices

• ✓The most common GST/VAT mistake: multiplying an inclusive price by the tax rate to find the tax component. This is wrong. If a price of $110 includes 10% GST, the GST is NOT $11 — it is $10. You must divide by 11 (or by 1.10) to get the correct answer. Our calculator does this correctly automatically.
• ✓Australia's GST-free items include most fresh food, medical services, residential rent, financial services, and exports. When calculating your BAS, ensure you correctly classify purchases as taxable, GST-free, or input-taxed — only taxable purchases generate input tax credits.
• ✓UK VAT has three rates: 20% standard (most goods and services), 5% reduced (domestic fuel, children's car seats, some renovation work), and 0% zero-rated (most food, children's clothing, books, public transport). VAT-registered businesses must charge the correct rate for each supply.
• ✓Canadian GST is 5% federally, but most provinces add a Provincial Sales Tax (PST) on top. Several provinces have combined them into a Harmonized Sales Tax (HST): Ontario 13%, BC 12%, Nova Scotia 15%, New Brunswick 15%, Newfoundland 15%. Our calculator shows federal GST only — for HST provinces, use the combined HST rate.
• ✓GST refunds for tourists: Australia allows tourists to claim GST back on purchases of A$300 or more from a single retailer within 60 days of departure, through the Tourist Refund Scheme at the airport. EU VAT refund thresholds vary by country but typically start around €50-€100.
• ✓New Zealand's 15% GST is one of the highest standard consumption tax rates in the OECD. Unlike Australia which has many GST-free categories, New Zealand's GST applies to virtually everything with very few exceptions, making the NZ GST system simpler but more comprehensive.
• ✓For UK businesses below the VAT registration threshold (£90,000 turnover in 2025), charging VAT is optional. However, voluntarily registering allows you to reclaim VAT on business purchases — beneficial if you buy significant amounts of goods from VAT-registered suppliers.
• ✓The reverse charge mechanism in the UK and EU means that for certain cross-border B2B services, the recipient accounts for the VAT rather than the supplier. This is important for digital services, construction, and certain professional services supplied across borders.

Who Uses This Calculator

Small business owners in Australia and NZ completing their quarterly BAS or GST return use the remove-tax function to find the GST component of bank statement totals, separating the tax from the total amount received or paid. UK freelancers and VAT-registered traders on the Flat Rate Scheme use the add-tax function to correctly invoice clients at the standard 20% VAT rate. E-commerce sellers on platforms like Shopify, eBay, and Amazon who ship to multiple countries need to calculate VAT or GST for each destination country's compliance requirements — our country selector makes this quick. Tourists visiting EU countries or the UK may be eligible for VAT refunds on purchases above certain thresholds — they use the remove-tax function to calculate how much VAT is in the receipt price they paid. Accountants reconciling supplier invoices that are quoted GST-inclusive verify the GST amount that should be on the tax invoice. Importers calculating duty and GST on imported goods, since Australian GST is applied to the value of the goods including customs duty. Landlords and property managers in Australia — residential rent is GST-free, but commercial rent is subject to GST, and the calculator helps verify correct invoicing. Restaurant and café owners in the UK pricing menus — food is VAT-zero-rated but restaurant meals attract 20% VAT on the full bill.