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CalculatorBuddy

Sales Tax Calculator

Calculate sales tax and the before- or after-tax price. Enter any two of the before-tax price, tax rate, and after-tax price to solve for the third.

Maintained by CalculatorBuddy TeamEditorial methodology

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After-Tax Price

ExampleSample values — edit any field to see your result.

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After-Tax Price

$106.50

Estimated result

Before-Tax Price
$100.00
Sales Tax Rate
6.500%
Sales Tax
$6.50

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Price vs tax

Before-tax price 94%, Sales tax 6%
  • Before-tax price94%
  • Sales tax6%

Compare scenarios

Keep a baseline, then change an assumption to see its effect side by side.

After-Tax Price$106.50

Work out sales tax and prices three ways. Enter any two of the before-tax price, the sales tax rate, and the after-tax price, and the calculator solves for the third along with the tax amount — including the reverse calculation of backing tax out of a total.

Choose the rate before calculating

This page solves the arithmetic after you supply a rate. It does not determine whether an item is taxable or which state, local, destination, origin, or special-district rate applies. Rates can also differ for food, lodging, vehicles, services, and exempt buyers. Use the current combined rate supplied by the relevant tax authority or seller.

Examples

$100 item at 6.5% tax

A $100 purchase at a 6.5% rate adds $6.50 of sales tax for an after-tax price of $106.50.

Backing tax out of a $106.50 total

Given a $106.50 total at 6.5%, the before-tax price is $106.50 ÷ 1.065 = $100.00, so the tax was $6.50.

Formula

All three modes rearrange one relationship between the before-tax price, the rate, and the after-tax total:

After-tax price = Before-tax price × (1 + rate)
Sales tax       = Before-tax price × rate
Before-tax price = After-tax price ÷ (1 + rate)
Tax rate        = (After-tax price ÷ Before-tax price) − 1
To remove tax from a total, divide by (1 + rate) — don't just subtract the rate. Subtracting 6.5% of the total slightly overstates the tax.
A mathematically correct result can still be the wrong tax if the rate or taxable price is wrong. Fees, discounts, shipping, and trade-ins may be treated differently by jurisdiction.

Frequently asked questions

How do I calculate sales tax?
Multiply the before-tax price by the tax rate (as a decimal). At a 6.5% rate, a $100 item has $100 × 0.065 = $6.50 of sales tax, for an after-tax price of $106.50.
How do I find the price before tax from a total?
Divide the after-tax total by one plus the tax rate. A $106.50 total at 6.5% is $106.50 ÷ 1.065 = $100.00 before tax. This "reverse" calculation is useful for backing tax out of a receipt total.
How do I find the tax rate from two prices?
Divide the after-tax price by the before-tax price and subtract one. If an item costs $100 before tax and $106.50 after, the rate is $106.50 ÷ $100 − 1 = 0.065, or 6.5%.
Which sales-tax rate should I enter?
Use the combined rate that applies to the specific transaction. State and local rates, product taxability, exemptions, sourcing rules, and special district taxes can all affect the amount. Confirm the rate with the relevant tax authority or the receipt; this calculator does not choose a jurisdiction.

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