VAT & Sales Tax Calculator (Add or Remove Tax)
Calculate and reverse VAT or sales tax instantly. Add tax (net to gross) or extract tax (gross to net) with pre-configured UK, EU, US, and global rates.
Global Standard VAT & Goods and Services Tax (GST) Rates
| Jurisdiction | Standard Rate | Tax System Name | Tax Authority / Ministry |
|---|---|---|---|
| United Kingdom | 20.0% | Value Added Tax (VAT) | HM Revenue & Customs (HMRC) |
| European Union (Avg) | 21.0% - 25.0% | VAT / TVA / IVA / MwSt | European Tax Commission |
| Australia | 10.0% | Goods and Services Tax (GST) | Australian Taxation Office (ATO) |
| Canada (Ontario) | 13.0% | Harmonized Sales Tax (HST) | Canada Revenue Agency (CRA) |
| United States | 0.0% - 10.25% | State & Local Sales Tax | State Department of Revenue |
💱 The Reverse Tax Math Trap
When extracting VAT from a gross receipt (e.g. £120 including 20% VAT), never multiply by 0.20 (which yields £24 and leaves £96 net, which is incorrect). Instead, divide the gross amount by 1.20: £120 / 1.20 = £100 net, with exactly £20 VAT.
About this tool
How to use it
- Select your calculation mode: 'Add Tax' (Net to Gross) or 'Remove Tax' (Gross to Net).
- Enter your starting amount and select or type your VAT/Sales tax percentage.
- Click 'Calculate VAT & Sales Tax' to see immediate exact breakdowns.
- Inspect the mathematical formula display, net base cost, and extracted tax amount.
Why it matters
Extracting tax from a gross receipt is a common accounting error because multiplying by the tax percentage produces incorrect figures. Using the official inverse formula Gross / (1 + r) guarantees bookkeeping and tax return compliance.
When to use it
Use this tool when generating B2B invoices, claiming back business expense receipts, filing quarterly VAT/GST returns, or calculating retail sales tax.
Good to know
Formulas: To Add Tax: Gross = Net × (1 + Rate); To Remove Tax: Net = Gross / (1 + Rate); Tax = Gross - Net.
Common questions
How do you calculate VAT backwards?
To extract VAT from a gross total, divide the gross amount by 1 plus the tax rate (e.g. For 20% VAT, divide by 1.20). The difference between the gross total and this net result is your exact VAT amount.
What is the difference between VAT and Sales Tax?
Value Added Tax (VAT) is collected incrementally at every stage of the supply chain by registered businesses. Sales Tax (like US state sales tax) is a single-stage tax levied only on the final consumer sale at checkout.
What are reduced VAT rates in the UK and EU?
Most nations apply reduced rates (e.g. 5% in the UK) to essential supplies like domestic energy, home insulation, children's car seats, and sanitary products, while standard goods incur 20%.
What is Australian GST?
Australia levies a broad 10% Goods and Services Tax (GST) on most goods, services, and other items sold or consumed in Australia, with basic food items and medical services exempt.