Sales Tax Calculator (US): Add or Remove Sales Tax
A sales tax calculator shows how much tax is added to a taxable purchase and the final amount due. It is useful for budgeting purchases when you already know the combined state and local sales tax rate.
Quick answer
Multiply the taxable price by the sales tax rate to estimate tax, then add that tax to the price. Local rates and taxable items vary, so use the rate that applies to the transaction.
At a glance
- What it calculates
- Calculate sales tax, the pre-tax price, and the final purchase total from a local tax rate.
- Who it is for
- US shoppers, freelancers and small businesses pricing taxable purchases when the combined state and local rate is known.
- Coverage
- United States (federal rules; state and local rules vary)
- Data and assumptions
- One combined state, county and city rate applied to the full taxable amount; exemptions, tax holidays and product-specific rules are not modelled.
- Cost
- Free, no signup, calculations run in your browser
- Last reviewed
- 2026-07-09
Calculator
How to use this calculator
- Enter the taxable purchase price.
- Enter the combined state and local tax rate.
- Review the tax amount and total purchase price.
Explanation
What it is
A sales tax calculator shows how much tax is added to a taxable purchase and the final amount due. It is useful for budgeting purchases when you already know the combined state and local sales tax rate.
How it works
The calculator converts the percentage rate to a decimal, multiplies it by the taxable price, and adds the result to the original price.
When to use it
Use it when you know the combined rate and need either the tax to add or the pre-tax price hidden inside a tax-inclusive total.
Limitations
- The calculator does not look up rates; you supply the combined rate.
- Product exemptions, sales tax holidays and marketplace facilitator rules are not applied.
- Five states have no statewide sales tax, and local rates change frequently.
Key terms
- Taxable price
- The portion of a purchase subject to sales tax.
- Combined rate
- The state, county, city, and district rates added together.
- Sales tax
- A transaction tax collected on taxable goods or services.
- Tax-inclusive total
- The amount paid after estimated tax is added.
Formula
The calculator converts the percentage rate to a decimal, multiplies it by the taxable price, and adds the result to the original price.
Worked example
For a $100 taxable purchase at 7.25%, estimated sales tax is $7.25 and the total is $107.25.
FAQ
How do I calculate sales tax on a purchase?
Multiply the taxable price by the tax rate expressed as a decimal. For a 7% rate, multiply by 0.07, then add the result to the price.
Why is the sales tax rate different by city?
State and local governments may impose separate rates, so the combined rate can vary by address and transaction location.
Are all products subject to sales tax?
No. Exemptions and reduced rates vary by state and product type, including food, medicine, clothing, and services.
Does this calculator find my local tax rate?
No. It calculates from the rate you enter. Confirm the applicable rate with the state or local revenue authority.
Can I calculate the pre-tax price from a tax-inclusive total?
This version starts with a pre-tax price. Divide an inclusive total by 1 plus the tax rate as a decimal to estimate the pre-tax amount.
How do I work out the price before sales tax?
Divide the tax-inclusive total by 1 plus the tax rate. A $107.50 total at a 7.5% combined rate is $107.50 ÷ 1.075 = $100.00 pre-tax, so the sales tax was $7.50.
How much is $1,299 plus tax?
At a 7% combined rate, $1,299 plus tax is $1,389.93 ($90.93 of tax). At 8.25% it is $1,406.17, and at 10% it is $1,428.90. Enter your own combined state and local rate for an exact figure.
Which states have no sales tax?
Alaska, Delaware, Montana, New Hampshire and Oregon have no statewide sales tax, though some Alaska localities levy their own. Every other state adds a state rate, and most allow county, city or district add-ons.
Common mistakes
- Applying the state rate only and missing local district add-ons.
- Using the buyer's rate when the state applies origin-based sourcing.
- Assuming every item on a receipt is taxable.
- Calculating tax on the post-discount price when the state taxes the pre-discount amount.
Tips
- Use the combined state, county, city and district rate for the delivery address.
- Work backwards from a receipt total to check the rate you were actually charged.
- Remember that origin and destination sourcing rules differ between states.
- Confirm whether groceries, clothing or services are taxed differently in your state.
Sources and editorial review
Educational estimates only; not personalized financial, tax, legal, lending, investment, or insurance advice.