01
Add tax to a price
Tax = net amount × rate ÷ 100
Gross amount = net amount + tax
At an example rate of 20%, an amount of 100.00 before tax has 20.00 tax and a total of 120.00.
Free tools
A clear answer to a quick tax calculation.
Add VAT, GST or sales tax to a price, or work backwards from a total. Enter your amount and tax rate. We’ll do the arithmetic.
Use a dot or comma for decimals, and spaces to group thousands.
Enter the percentage that applies to your transaction.
An example is filled in. Replace it with your own figures.
Your calculation
Including tax
USD 120.00
- Before tax
- USD 100.00
- Tax amount (20 %)
- USD 20.00
- Including tax
- USD 120.00
Rounded to 2 decimal places for this currency. Calculated once on the whole amount. Rounding each invoice line separately can give a different total.
Create a free invoice
Calculated in your browser. No account needed.
From one price to the full picture.
Choose whether your starting amount includes tax. The calculator shows the price before tax, the tax itself and the final total together.
02
Remove tax from a total
Net amount = gross amount ÷ (1 + rate ÷ 100)
Tax = gross amount − net amount
If 120.00 already includes 20% tax, the amount before tax is 100.00 and the tax is 20.00. Subtracting 20% of 120.00 would give the wrong base.
Read the calculation method: HMRC’s VAT calculation guidance.
Your rate. Your currency.
The 20% rate is an example, not a rate selected for your country or business. Enter the rate that applies to your transaction. Currency changes the display and decimal precision; it does not convert amounts or determine tax rules.
Tax is calculated on one total, with half-up rounding to the currency’s decimal precision: for example, 2 places for USD/EUR, 0 for JPY and 3 for TND. For an inclusive price, the net amount is rounded first and tax is the difference. An invoice that rounds each line can differ slightly.
A few useful answers.
Is this tax calculator free?
Yes. Use it without an account or payment. The calculation happens in your browser, and the figures you enter are not sent to a server by this calculator.
Can I use it for VAT, GST and sales tax?
Yes, for a single percentage tax applied to an amount. Enter your applicable rate. It does not determine registration, exemptions, compound taxes, income tax or filing obligations.
How do I calculate tax from a tax-inclusive price?
Choose Remove tax, enter the total including tax and enter the rate. The net amount is the total divided by 1 plus the rate divided by 100. Tax is the difference between gross and net.
Can I enter a decimal tax rate?
Yes. Rates from 0% to 100% are supported, with up to four decimal places. Use a dot or comma as the decimal separator, for example 8.875 or 8,875.
Why can my invoice total differ by a cent?
This calculator rounds once on the whole amount. Some invoices calculate and round tax separately on each line, so adding those rounded line amounts can produce a slightly different total.
Put the numbers on an invoice.
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