Reverse VAT & Sales Tax Calculator
Enter a tax-inclusive or tax-exclusive price and instantly get the net amount, the exact tax amount, and the gross price — for any VAT or sales tax rate.
Entered amount is the tax-inclusive (gross) price.
Net (excl. tax)
$100.00
Tax amount
$20.00
Gross (incl. tax)
$120.00
About this tool
How to use it
- Choose whether the amount you're entering already includes tax (gross/tax-inclusive) or doesn't (net/tax-exclusive) — this changes which formula is used.
- Enter the amount and the tax rate (use a preset for a common VAT rate, or type your own).
- Read all three figures together: net, tax amount, and gross — whichever one you didn't enter is calculated from the other two.
- Click Calculate, or just keep typing — everything updates live.
Why it matters
A price that includes tax and the same price without tax look like two different, unrelated numbers unless you do the reverse-percentage math correctly — and reversing a percentage isn't just subtracting it (a $120 price with 20% tax included isn't $96 pre-tax, it's $100, because the 20% was added to the smaller number, not the larger one). Getting this backwards is a common bookkeeping and pricing mistake.
When to use it
Working out how much of a receipt or invoice total is tax versus the actual price of the goods or service, for expense reports or accounting. Pricing a product to hit a specific tax-exclusive target once tax is added. Checking a supplier's or invoice's tax breakdown adds up correctly.
Good to know
The reverse calculation from a gross (tax-inclusive) price is net = gross ÷ (1 + rate), not gross × (1 − rate) — dividing, not subtracting, because the tax rate applies to the net amount, not the gross amount. The forward calculation from a net price is the more familiar tax = net × rate, gross = net + tax. This tool doesn't know which country's or region's VAT/sales tax rules apply to your situation (exemptions, reduced rates, reverse charges) — the preset rates are each country's real statutory standard VAT rate at the time this tool was built, but always confirm the applicable rate for your specific case.
Common questions
Why isn't the tax amount just gross × rate?
Because the rate applies to the net (pre-tax) amount, not the gross (tax-inclusive) amount — multiplying the gross price by the rate over-counts the tax. The correct reverse formula divides first: net = gross ÷ (1 + rate), then tax = gross − net.
What's the difference between 'gross' and 'net'?
Net is the price before tax is added (what a business actually earns from the sale). Gross is the price after tax is added (what the customer actually pays). Tax is the difference between the two.
Are the preset tax rates accurate for my country?
The VAT presets shown are each country's real statutory standard rate at the time this tool was built, but VAT/sales tax systems commonly have reduced rates for specific goods, exemptions, and periodic rate changes — always confirm the exact rate that applies to your specific transaction.
Can I use this for US sales tax, not just VAT?
Yes — the math is identical (sales tax and VAT are both a percentage applied to a net amount), the only difference is that sales tax varies by state/city rather than being one national rate, so you'll need to enter your local combined rate rather than use a preset.
Is this financial or tax advice?
No — this is a plain arithmetic tool for splitting a price into its tax and non-tax components. It isn't a substitute for professional tax advice on which rate, exemption, or rule applies to your specific situation.