HesapHanem

Reverse Sales Tax Calculator

Find the pre-tax price from a gross amount.

How it is calculated

When a price already includes sales tax or VAT, the pre-tax amount is net = gross / (1 + rate/100) and the tax is tax = gross − net. Enter the tax-inclusive price (gross) and the tax rate as a percentage. Dividing is the key step: you cannot simply subtract the rate percentage from the gross, because the tax was added on top of the net, not on top of the gross. The tool accepts a rate of 0 and any non-negative amounts. It applies the single rate you enter; it does not know which rates apply in your country or to your product, and mixed-rate baskets need to be split by hand. Results are shown in dollars to the cent.

Worked example

A receipt shows a total of 120 including a 20% tax. The divisor is 1 + 20/100 = 1.20. Net price: 120 / 1.20 = $100.00. Tax portion: 120 − 100 = $20.00. Note that subtracting 20% of 120 would give 96, which is wrong.

Try this example →

Common mistakes

  • Subtracting the rate percentage from the gross (120 × 0.80 = 96) instead of dividing by 1.20.
  • Entering a price that does not include tax as the gross figure.
  • Using the wrong rate, for example a reduced rate for an item that carries the standard rate.
  • Applying one rate to a bill that mixes taxed and exempt items.
  • Entering the rate as a decimal (0.2) rather than as a percentage (20).

Sources

About this calculator

Given a tax-inclusive (gross) price and the tax rate, this calculator works backward using net = gross / (1 + taxRate) to split the amount into the pre-tax price and the tax portion — the opposite direction from a normal sales tax calculation, which adds tax onto a known net price.

Retailers and accountants use it to recover the net revenue and tax collected from a receipt total, freelancers use it to figure out how much of an invoice total is actual income versus VAT/GST owed to the government, and shoppers use it to see how much tax they actually paid on a purchase. The calculator handles any tax rate you enter, so it works for VAT, GST, or standard US-style sales tax alike.

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Comments (1)

  • Editorial team

    The result is rounded to the cent, so working a multi-item receipt line by line can differ by a cent or two from running the receipt total once. When you need figures that match an invoice, follow the rounding rule your accounting software or tax authority uses. Turkish KDV commonly appears at 20, 10 and 1 percent, so enter the rate printed on your document. Which rate do you usually work with?

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