Sales Tax Calculator

Calculate sales tax and total purchase costs with support for discounts, additional fees, and tax rates from all US states.

What Is a Sales Tax Calculator?

A sales tax calculator computes the tax amount and total price for a purchase based on the item price and the applicable tax rate. It can also perform reverse calculations, extracting the pre-tax price and tax amount from a total that already includes tax. This simple tool is useful for budgeting, price comparisons, expense tracking, and verifying receipts.

Sales tax is one of the most common taxes consumers encounter. Unlike income tax, which is deducted from earnings, sales tax is added at the point of purchase and affects every taxable transaction. Rates vary by state, county, and city, making it important to use the correct combined rate for your location.

How Sales Tax Math Works

The forward calculation is straightforward multiplication:

Tax Amount = Price x (Tax Rate / 100)

Total Price = Price + Tax Amount

For example, a $250 purchase at 7.5% tax: Tax = $250 x 0.075 = $18.75. Total = $250 + $18.75 = $268.75.

The reverse calculation extracts the original price from a tax-inclusive total:

Pre-Tax Price = Total / (1 + Tax Rate / 100)

Tax Paid = Total - Pre-Tax Price

For example, a $268.75 total at 7.5% tax: Pre-Tax = $268.75 / 1.075 = $250.00. Tax = $268.75 - $250.00 = $18.75.

The calculator also generates a quick reference table showing tax and total amounts for common price points at your specified rate, saving time for repeated lookups.

How to Use This Calculator

Enter the pre-tax price. This is the sticker price or listed price of the item before any tax is added.
Enter your sales tax rate. Use the combined rate that includes both state and local taxes. Check your most recent receipt or search for your location's rate if unsure.
Review the forward calculation. The results show the tax amount and the total price you will pay. The quick reference table provides instant lookups for common purchase amounts at your rate.
Use the reverse calculation if needed. Enter a total price (tax already included) in the optional field to find the original pre-tax price and the tax portion. This is helpful for expense reports and receipt verification.

Worked Examples

Example 1: Standard Purchase

A $49.99 item at 8.25% tax. Tax is $49.99 x 0.0825 = $4.12. Total is $54.11. The tax adds roughly $4 to a $50 purchase.

Example 2: Large Purchase

A $1,200 laptop at 9.5% tax. Tax is $1,200 x 0.095 = $114.00. Total is $1,314.00. On large purchases, tax becomes a significant dollar amount worth budgeting for.

Example 3: Reverse from Receipt

A restaurant receipt shows a $86.40 total. The local combined tax rate is 8.0%. Pre-tax amount: $86.40 / 1.08 = $80.00. Tax paid: $6.40. This confirms the base bill was $80 before tax.

Example 4: Comparing Tax Across Locations

The same $500 item in two locations: City A at 6.0% tax ($30 tax, $530 total) vs City B at 10.25% tax ($51.25 tax, $551.25 total). The $21.25 difference shows why some shoppers cross borders for large purchases.

Tips and Common Mistakes

Always use the combined rate. Many people enter only the state rate and forget the local portion. Your actual rate is the state rate plus any county, city, and special district taxes combined.

Check if your item is exempt. Groceries, prescription drugs, and certain clothing may be exempt or taxed at a reduced rate in your state. Applying the standard rate to exempt items overstates the tax.

Budget for tax on large purchases. A 10% tax rate on a $2,000 purchase adds $200. Include estimated tax when setting a budget for major purchases like electronics, furniture, or appliances.

Verify receipts with the reverse calculator. Occasionally businesses apply incorrect tax rates. The reverse calculator lets you check whether the tax charged on a receipt matches the expected rate for your area.

Note that tax applies to the pre-tax price only. Sales tax is not compounded. If you pay separate taxes (for example, a tourism tax and a sales tax), each is calculated on the original price, not on the price plus the other tax, unless local law specifies otherwise.

Track sales tax for deductions. If you itemize deductions on your federal tax return, you may deduct either state income tax or state and local sales tax paid. Keeping records of large purchases and their tax amounts can increase your deduction.

Frequently Asked Questions

How is sales tax calculated?

Sales tax is calculated by multiplying the pre-tax price by the tax rate expressed as a decimal. For example, an item priced at $100 with a sales tax rate of 8.25% has a tax of $100 x 0.0825 = $8.25. The total price is $100 + $8.25 = $108.25. The tax amount is always applied to the pre-tax price, not to other taxes or fees.

How do I find the pre-tax price from a total?

To reverse-calculate the pre-tax price from a total that includes tax, divide the total by (1 + tax rate as a decimal). For example, if the total is $108.25 and the tax rate is 8.25%, the pre-tax price is $108.25 / 1.0825 = $100.00. This is useful when a receipt shows only the total paid.

What is the average sales tax rate in the US?

The average combined state and local sales tax rate in the United States is approximately 8.5% as of 2026, though rates vary significantly by location. State rates range from 0% (Delaware, Montana, New Hampshire, Oregon, Alaska at the state level) to 7.25% (California). Local jurisdictions can add additional taxes, pushing combined rates above 10% in some areas.

Are all items subject to sales tax?

No. Most states exempt certain categories from sales tax. Common exemptions include groceries (in many states), prescription medications, and clothing (in some states like Pennsylvania and New Jersey). Digital goods, services, and prepared foods have varying treatment depending on the state and locality.

Do I need to pay sales tax on online purchases?

Yes. Following the 2018 Supreme Court decision in South Dakota v. Wayfair, states can require out-of-state sellers to collect and remit sales tax. Most major online retailers now charge sales tax based on the buyer's shipping address. If a seller does not collect the tax, the buyer is technically responsible for paying use tax directly to their state.

How do combined state and local taxes work?

Many purchases are subject to both a state sales tax and a local sales tax (county, city, or special district). These are added together to form the combined rate. For example, a state rate of 6% plus a city rate of 2.25% equals a combined rate of 8.25%. Enter the combined rate in the calculator for the most accurate result.

What is use tax?

Use tax is a complement to sales tax that applies when a taxable item is purchased without paying sales tax, typically from an out-of-state seller. The use tax rate is usually identical to the sales tax rate. States expect residents to self-report and pay use tax on untaxed purchases, though compliance varies.

Do sales tax rates change?

Yes. State and local governments can adjust sales tax rates through legislation. Rates may increase or decrease, and new local taxes can be added through voter referendums or government action. It is a good practice to verify your local rate periodically, especially before making large purchases where even a small rate difference matters.