Sales Tax Calculator: Add Tax to a Price
Use this sales tax calculator to enter a pre-tax price and combined rate, then calculate the tax amount and final total. The result is instant, transparent, and easy to check against a receipt, quote, or spreadsheet.
Sales Tax Calculator
InstantEnter the taxable price and the combined rate. The page calculates the sales tax amount and total with tax directly in your browser.
Sales Tax Calculator Results
The calculator separates the original price, the sales tax amount, and the final customer total.
Formula used
-Use the combined rate
A checkout rate may combine state, county, city, transit, and special-district taxes. Enter the total rate that applies to the taxable sale.
This is arithmetic, not a live rate lookup
The calculator accepts the rate you provide. It does not maintain a live address-based tax database, so verify current rates with an official or trusted local source.
Rounding can differ by register
A store may round tax by line item, invoice, or subtotal. A one-cent difference can occur even when the formula is correct.
Taxability still matters
Discounts, shipping, tax-exempt items, and product-specific rules can change the taxable base. Use the taxable price rather than the list price when needed.
Need to work backward from a tax-inclusive total? Use the reverse sales tax calculator to find the pre-tax price and tax inside the total.
Sales Tax Calculator Examples
Use these examples to check the difference between the pre-tax price, the tax amount, and the final total.
$100 at 8% sales tax
$100 × 8% = $8 tax, so the final total is $108.
$50 at 8.875% sales tax
A three-decimal combined rate adds $4.44 tax to a $50 price, for a $54.44 total after rounding.
$75 at 0% sales tax
When the rate is 0%, the tax amount is $0 and the total stays $75.
$19.99 at 7.25% sales tax
Small purchases show how fractional cents are rounded to a two-decimal currency result.
How to Use the Sales Tax Calculator
You only need the taxable price and the combined sales tax rate for the sale.
Enter the pre-tax price
Enter the amount that is subject to sales tax before tax is added. If there is a discount, use the taxable discounted price when appropriate.
Enter the sales tax rate
Enter the combined percentage for the sale location, such as 8, 7.25, or 8.875.
Calculate the total
Select Calculate sales tax to see the tax amount, final total, rate used, and formula.
Check the rate and rounding
Compare the rate with the receipt, checkout page, or official local lookup. Registers can round line items differently.
Sales Tax Formula
Sales tax is calculated from the price before tax, not from the final total.
Find the tax amount
Sales tax = price before tax × (tax rate / 100)
For $100 at 8%, the tax is $100 × 0.08 = $8.
Find the total with tax
Total = price before tax + sales tax
Add the calculated tax to the original taxable price.
Convert a percentage to a decimal
Decimal rate = sales tax percent / 100
For example, 8.25% becomes 0.0825 in the multiplication step.
Work backward from an inclusive total
Pre-tax price = total / (1 + tax rate / 100)
Use the reverse sales tax calculator when the amount you have already includes tax.
Which Sales Tax Rate Should You Enter?
Sales tax rates depend on location and the type of item or service. This general state tax calculator accepts any combined rate you have verified, but it does not replace an address-based lookup.
| Situation | Rate source | What to check |
|---|---|---|
| In-store receipt | Use the rate printed on the receipt or divide tax by the taxable subtotal. | This is usually the clearest source when every item used the same rate. |
| Online checkout | Use the checkout rate for the ship-to address. | Shipping, marketplace rules, exemptions, and product type can change the taxable base. |
| Business quote | Use the combined rate for the sale location. | Keep different jurisdictions separate when you are preparing accounting records. |
| Mixed taxable and exempt items | Calculate each taxable group separately when rates or exemptions differ. | Do not apply one rate to exempt items just because they appear on the same receipt. |
| State or local rate lookup | Verify the combined rate with an official state, county, city, or local source before entering it. | A tax calculator can apply the rate you provide, but the correct rate depends on jurisdiction, address, product, and exemptions. |
This page does not maintain a live tax-rate database. Use the linked state or local resources for an exact current rate.
Sales Tax Calculator Edge Cases
These details explain why a calculated total may differ from a receipt or accounting report by a few cents.
0% tax rate
A zero rate is valid for a tax-exempt sale or a scenario where no tax is being added. The total equals the pre-tax price.
Discounts and coupons
If a discount reduces the taxable base, calculate sales tax from the discounted taxable amount rather than the original list price.
Shipping and fees
Shipping, service fees, deposits, and marketplace charges may have different tax treatment. Include only amounts that belong in the taxable price.
Multiple rates or exemptions
Separate taxable groups when items have different rates or exemptions. A single blended rate can hide the real tax owed.
One-cent rounding differences
Some systems round each item while others round the subtotal. Compare the rounding method before treating a small difference as an error.
Sales Tax Rate Sources
Use these resources when you need to verify a current location-based rate instead of entering an estimate.
Avalara Sales Tax Rate Calculator
Address-based US sales tax lookup and rate guidance. This page is an external reference, not part of the calculator result.
Open sourceMinnesota Sales Tax Rate Calculator
Official state example of a location-specific sales tax rate lookup.
Open sourceCalifornia Sales and Use Tax Rates
Official state rate table and lookup entry point for California sales and use tax rates.
Open sourceSales Tax Calculator FAQ
Answers to common questions about adding sales tax, finding the rate, and checking the final total.
Add tax before you send the quote
Enter the taxable price and combined rate, then copy the tax amount and final total into your receipt check, quote, or spreadsheet.