Sales Tax Calculator

Calculate sales tax and the final price, or reverse-calculate the pre-tax price from a tax-inclusive total.

Your tax result will appear here.

About the Sales Tax Calculator

At checkout, a tax percentage becomes a real currency amount added to the taxable price. This calculator can add that tax to a pre-tax amount or reverse a tax-inclusive total when the applicable rate is known.

Tax rules are location- and product-specific. The arithmetic is simple, but the correct rate and taxable amount may depend on local law, exemptions, discounts and how the transaction is structured.

How to Use the Sales Tax Calculator

  1. Enter the pre-tax price or tax-inclusive total according to the mode you are using.
  2. Enter the sales-tax rate that applies to the location and item.
  3. For reverse calculations, confirm that the entered total truly includes tax at that single rate.
  4. Calculate the tax and final price, then use official local rules for questions about whether an item is taxable.

How the Calculation Works

Tax amount = taxable price × tax rate ÷ 100. Tax-inclusive total = taxable price + tax amount.

When working backward from a total that includes tax, pre-tax price = total ÷ (1 + tax rate/100), and tax is the difference between total and pre-tax price.

Worked example

Sales Tax Calculator Worked Example

8.25% tax on $120

Tax = $120 × 0.0825 = $9.90. Total price = $120 + $9.90 = $129.90.

Result guide

Understanding Your Sales Tax Calculator Result

The result is the arithmetic for the rate and taxable amount entered. It does not determine which rate or exemption legally applies to a specific sale.

Before you rely on the answer

Assumptions and Limitations

  • The tax rate is correct for the transaction.
  • The entered price uses the correct taxable base.
  • Multiple local taxes are already represented in the combined rate when appropriate.

Practical tip

Using This Result in Practice

For a purchase with discounts, determine whether the local rule taxes the original price or discounted price before calculating. Do not assume every jurisdiction handles coupons and rebates the same way.

Common questions

Sales Tax Calculator FAQ

How do I remove sales tax from a total?

Divide the tax-inclusive total by 1 plus the tax rate as a decimal, then subtract the pre-tax amount from the total to find the tax.

Should tax be calculated before or after a discount?

That depends on the applicable tax rule and promotion type. Use the taxable amount required by the jurisdiction.

Can the calculator tell me the correct tax rate?

No. Rates and taxable categories change by location and transaction, so use an official tax source for the rate itself.