How much tax is added to a net price, or included inside a gross price?

Sales tax can be added to a tax-exclusive price or extracted from a tax-inclusive total. Those are different operations because tax inside a gross amount is not simply gross price multiplied by the headline rate.

Choosing the correct tax base

Treating the amount as net: Tax = Amount × Rate ÷ 100 Gross = Amount + TaxTreating the amount as gross: Net = Amount ÷ (1 + Rate ÷ 100) Tax = Amount − Net

Net, tax and gross on one transaction

The worked figures follow the mode represented by the calculator inputs and show the net amount, tax amount and gross amount as separate values.

Illustrative inputs; currency amounts below use USD. Rates and prices are assumptions, not live quotes.

Amount
$1,000.00
Tax rate
20%

Step-by-step calculation

  1. If 1,000 is pre-tax: tax = 1,000 × 20 ÷ 100 = 200, giving 1,200 gross.
  2. If the same 1,000 already includes tax: net = 1,000 ÷ (1 + 20 ÷ 100) = 833.333333.
  3. Embedded tax = 1,000 − 833.333333 = 166.666667. These are alternative interpretations of the input, not two taxes charged together.

Intermediate figures are rounded for reading. Results use the full calculation precision.

Price with tax added$1,200.00
Tax added$200.00
Price with tax removed$833.33
Tax already inside$166.67

Why inclusive tax uses division

When tax is added, the net amount is the base. When tax is extracted, the gross amount already contains both base and tax, so the divisor must include the rate.

Rates and rounding beyond a single-tax model

Do not subtract the tax percentage directly from a tax-inclusive price. That produces a different base because percentages depend on their denominator.

  • One tax rate applies to the complete amount.
  • All amounts use the same currency and rounding convention.
  • Compound taxes, exemptions and jurisdiction-specific rules are excluded.

Calculations related to vat and sales tax

The following tools examine neighbouring parts of the same calculation without changing the inputs or assumptions used above.

References

Sources and conventions

Quick answers

Frequently asked questions

How do I add VAT or sales tax to a net price?

Treat the entered amount as net; the calculator multiplies it by the tax rate and adds that tax.

How do I remove VAT from a tax-inclusive price?

Treat the amount as gross; net price is gross divided by one plus the tax rate as a decimal.

Why is tax inside a gross price smaller than gross price times the rate?

Because the tax rate applies to the net base, not to the already tax-inclusive total.

Calculation method and limitations · Report an error

Educational content only. This guide is not financial advice.