Sales Tax Calculator
Calculate sales tax from price or find the before-tax price from a total. Real-time calculations with visual breakdown.
Results
Total (After Tax)
$108.00
$108.00
Total
Before-Tax Price
Sales Tax
Before-Tax Price
$100.00
Sales Tax
$8.00
After-Tax Total
$108.00
Summary
Tax Rate
8%
Tax Multiplier
1.08
Tax as % of Total
7.41%
Calculation Mode
Forward
Understanding Sales Tax Calculations
Calculate Tax Amount
Tax = Price x (Rate / 100)
Multiply the before-tax price by the tax rate (as a decimal) to get the tax amount. Example: $100 x 0.08 = $8 tax.
Calculate Total Price
Total = Price x (1 + Rate/100)
Multiply the before-tax price by the tax multiplier. Example: $100 x 1.08 = $108 total.
Find Before-Tax Price
Price = Total / (1 + Rate/100)
Divide the total by the tax multiplier to find the original price. Example: $108 / 1.08 = $100 before tax.
Frequently Asked Questions
To calculate sales tax, multiply the before-tax price by the tax rate (as a decimal). For example, if an item costs $100 and the tax rate is 8%, the tax is $100 x 0.08 = $8. The total price would be $108.
To find the before-tax price, divide the total by (1 + tax rate as decimal). For example, if the total is $108 with 8% tax: $108 / 1.08 = $100 before tax. This is called a "reverse sales tax calculation."
The average combined state and local sales tax rate in the US is approximately 7.12%. However, rates vary significantly by state - from 0% in states like Oregon and Montana to over 10% in some areas when combining state and local taxes. Always check your local rate for accurate calculations.
Five US states have no state sales tax: Alaska, Delaware, Montana, New Hampshire, and Oregon. However, Alaska allows local governments to charge sales tax, so some areas in Alaska do have local sales taxes. These states often rely more heavily on income or property taxes instead.