How to use the VAT and GST calculator
- Add tax: enter a price before tax and the rate to get the tax amount and the price including tax.
- Remove tax: enter a price that already includes tax to find the price before tax and how much tax it contains.
- Type any rate, or tap a quick rate for a country's standard rate. It works the same way for VAT, GST, HST or sales tax.
Formulas
Adding tax: Tax = Net price × Rate ÷ 100, Gross price = Net price + Tax
Removing tax: Net price = Gross price ÷ (1 + Rate ÷ 100), Tax = Gross price − Net price
Worked examples
Adding 20% VAT: a 100 item costs 100 × 20% = 20 in tax, so the price including VAT is 120.
Removing 10% GST: a receipt shows 1,100 including GST. The price before GST is 1,100 ÷ 1.10 = 1,000, so the GST included is 100.
The most common mistake: taking the rate off the gross price
To remove 20% VAT from 120, it's tempting to take 20% off: 120 × 0.8 = 96. That's wrong, because the 20% was added to 100, not to 120. Divide by 1.2 instead: 120 ÷ 1.2 = 100. The tax included in a gross price is always a smaller share than the rate: 20% VAT is 16.67% of the gross price, and 10% GST is 9.09%.
Standard VAT and GST rates by country
These are the main (standard) rates, checked on 29 October 2026. Many countries also have reduced or zero rates for things like food, books or energy, and rates can change, so confirm the rate for your product with the tax authority.
| Country | Tax | Standard rate | Source |
|---|---|---|---|
| United Kingdom | VAT | 20% (reduced 5%, zero 0%) | FreeAgent VAT rates |
| Ireland | VAT | 23% (reduced 13.5% and 9%) | PwC Tax Summaries |
| Australia | GST | 10% | Australian Taxation Office |
| New Zealand | GST | 15% | Australian Taxation Office |
| Singapore | GST | 9% (since 1 January 2024) | ClearTax Singapore |
| Canada | GST / HST | GST 5%; HST 13% Ontario, 14% Nova Scotia, 15% New Brunswick, Newfoundland and Labrador, Prince Edward Island. Some provinces add PST or QST. | Canada Revenue Agency |
| United Arab Emirates | VAT | 5% (since 1 January 2018) | UAE Government portal |
| India | GST | Main slabs 5% and 18%, plus 40% for specified luxury and harmful goods (since 22 September 2025) | Cashfree GST rates |
| United States | Sales tax | No national rate. States, counties and cities set their own, so enter your combined local rate. | Your state's revenue department |
Frequently asked questions
What's the difference between VAT, GST and sales tax?
VAT and GST work the same way: tax is charged at each stage of the supply chain, and businesses can usually reclaim the tax they pay on their own purchases. Sales tax, as in the US, is normally charged only on the final sale to the customer. For a single price, the maths is identical, so this calculator works for all three.
How much of a price is VAT?
Divide the rate by (100 + rate). At 20% VAT, 20 ÷ 120 = 16.67% of the price including VAT is tax. At 10% GST, it's 10 ÷ 110 = 9.09%.
Should my prices include tax?
It depends on where you sell. In the UK, EU, Australia and New Zealand, prices shown to consumers usually must include VAT or GST. In the US and Canada, prices are usually shown before tax and the tax is added at checkout. Check the rules where your customers are.
Can I use this for HST and PST in Canada?
Yes. Use the HST rate on its own in HST provinces. In provinces with GST and PST, add the two rates together when both apply to the same price, for example 5% + 7% = 12% in British Columbia.
Formulas checked 29 October 2026. This calculator is for planning and education, not financial, tax or legal advice.