The two formulas that work everywhere
To add tax to a net price, multiply by one plus the rate: net × 1.20 for 20% VAT. To remove tax from a price that already includes it, divide by the same number: gross ÷ 1.20. The tax itself is then gross minus net.
Another way to find the tax inside a gross price is the tax fraction: rate ÷ (100 + rate). For 20% VAT that is 20/120, which simplifies to 1/6. For Australian GST it is 10/110 = 1/11, and for New Zealand GST 15/115 = 3/23.
Taking 20% off a VAT-inclusive price does not remove the VAT. On £120, taking 20% off gives £96.00, but the real pre-VAT price is £100.00. VAT is 20% of the net price, not 20% of the gross price, so the tax inside a gross price is always one sixth, not one fifth.
Multiplier and tax fraction for every rate
Use the multiplier to add tax, the divisor to remove it, and the fraction to pull the tax amount straight out of a gross price.
| Tax | Rate | Add tax | Remove tax | Fraction of gross | Share of gross |
|---|---|---|---|---|---|
| UK VAT standard | 20% | × 1.20 | ÷ 1.20 | 1/6 | 16.67% |
| UK VAT reduced | 5% | × 1.05 | ÷ 1.05 | 1/21 | 4.76% |
| Australia GST | 10% | × 1.10 | ÷ 1.10 | 1/11 | 9.09% |
| New Zealand GST | 15% | × 1.15 | ÷ 1.15 | 3/23 | 13.04% |
| Canada GST (Alberta) | 5% | × 1.05 | ÷ 1.05 | 1/21 | 4.76% |
| Canada HST (Ontario) | 13% | × 1.13 | ÷ 1.13 | 13/113 | 11.50% |
| Canada HST (Nova Scotia) | 14% | × 1.14 | ÷ 1.14 | 7/57 | 12.28% |
| Canada HST (NB, NL, PEI) | 15% | × 1.15 | ÷ 1.15 | 3/23 | 13.04% |
UK VAT rates in 2026
Zero-rated is not the same as exempt. A business selling zero-rated goods still records them as taxable sales and can usually reclaim VAT on its costs; exempt sales are outside the VAT system.
| Rate | VAT | Applies to (examples from GOV.UK) |
|---|---|---|
| Standard | 20% | Most goods and services |
| Reduced | 5% | Some goods and services, for example children’s car seats and home energy |
| Zero | 0% | Zero-rated goods and services, for example most food and children’s clothes |
Removing 20% VAT: quick reference
| Price including VAT | Price excluding VAT | VAT included |
|---|---|---|
| £10.00 | £8.33 | £1.67 |
| £50.00 | £41.67 | £8.33 |
| £100.00 | £83.33 | £16.67 |
| £120.00 | £100.00 | £20.00 |
| £250.00 | £208.33 | £41.67 |
| £500.00 | £416.67 | £83.33 |
| £1,000.00 | £833.33 | £166.67 |
| £1,200.00 | £1,000.00 | £200.00 |
When a UK business must register for VAT
You must register if your VAT-taxable turnover for the last 12 months goes over £90,000, or if you expect it to go over £90,000 in the next 30 days alone. In the first case you must register within 30 days of the end of the month in which you went over. Below the threshold, registering is voluntary.
Australia and New Zealand GST
Australian GST is 10%. To find the GST in a GST-inclusive price, divide by 11: a $110 item includes $10 GST. Use our Australian GST calculator for any amount.
New Zealand GST is 15%. The GST inside a GST-inclusive price is 3/23 of it, so a $115 item includes $15 GST. Use our New Zealand GST calculator.
Canada: GST, HST, PST and QST
Canada is more complex because the rate depends on the province and can have two parts. Each part is charged on the pre-tax price, so you add the rates together before using the formulas above. See the full province-by-province breakdown in our Canada GST/HST guide.
Canada GST/HST calculatorDoing it with a percentage calculator
If you only need a quick check, our percentage calculator can add or subtract a percentage. Remember that removing VAT is not "minus 20%": use a divisor of 1.2, or a percentage decrease of 16.67%.
Frequently asked questions
How do I remove 20% VAT from a price?
Divide the price by 1.2. For example, £240 ÷ 1.2 = £200 before VAT, so the VAT is £40.
Why is the VAT fraction 1/6 and not 1/5?
Because VAT is 20% of the net price. A VAT-inclusive price is 120% of the net price, and 20/120 equals 1/6.
How do I calculate the GST in an Australian price?
Divide the GST-inclusive price by 11. A price of $55 includes $5 GST.
What is 3/23 in New Zealand GST?
It is the share of a GST-inclusive price that is GST at 15%: 15/115 simplifies to 3/23.
What is the UK VAT registration threshold?
£90,000 of VAT-taxable turnover in a rolling 12-month period, or if you expect to exceed £90,000 in the next 30 days alone.
Official sources
- GOV.UK — VAT rates
- GOV.UK — Register for VAT
- Australian Taxation Office — GST
- Inland Revenue (NZ) — GST
- Canada Revenue Agency — GST/HST calculator (and rates)
Rates checked against these sources on 30 October 2026. Tables are calculated with the same engines as our calculators. This guide is general information, not tax advice.
About the author: Ahmed Bilal
Ahmed Bilal is the founder of VolexTool and builds and maintains every calculator on the site. Tax rates and thresholds are taken directly from official sources such as GOV.UK, HMRC, the Canada Revenue Agency and the Australian Taxation Office, the formula is shown on every page, and each update must pass more than 600 automated checks before it goes live. Ahmed is not a tax adviser: for decisions about your own situation, speak to a qualified accountant or financial adviser.