Choose Calculation Mode
Select Add Sales Tax to calculate a final tax-inclusive price or Remove Sales Tax to find the pre-tax amount.
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Free Online Tax Calculator
Sales Tax Calculator Add or Remove Sales Tax Instantly
Calculate sales tax, total price after tax, pre-tax price and tax amount using any custom tax rate with our free online sales tax calculator.
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Add Sales Tax
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Remove Sales Tax
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Custom Tax Rates
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Multiple Currencies
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Instant Results
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Free Tool
Sales Tax Calculator
Calculate tax-inclusive and tax-exclusive prices
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Enter the price before sales tax
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Enter the applicable sales tax percentage
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Add Sales Tax Formula
Tax Amount = Price × (Tax Rate ÷ 100)
Total Price = Price + Tax Amount
Simple Process
How to Use the Sales Tax Calculator
Calculate sales tax in three simple steps.
Enter Price & Tax Rate
Enter the applicable amount and sales tax percentage. You can also choose a quick rate or select your preferred currency.
View Tax Breakdown
See the tax amount, pre-tax price, final total and a clear breakdown of the calculation.
Tax Formulas
Sales Tax Calculation Formulas
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Add Sales Tax Formula
To calculate tax from a pre-tax price, multiply the price by the tax rate expressed as a decimal.
Tax = Price × (Rate ÷ 100)
Total = Price + Tax
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Remove Sales Tax Formula
To find the pre-tax amount from a total that already includes tax, divide the total by one plus the decimal tax rate.
Pre-Tax = Total ÷ (1 + Rate ÷ 100)
Tax = Total − Pre-Tax
Examples
Sales Tax Calculation Examples
Example: 5% Tax
For a $100 pre-tax price with a 5% tax rate:
Tax Amount
$5.00
Total Price
$105.00
Example: 8.25% Tax
For a $100 pre-tax price with an 8.25% tax rate:
Tax Amount
$8.25
Total Price
$108.25
Example: Reverse Tax
For a $108.25 tax-inclusive total at 8.25%:
Pre-Tax Price
$100.00
Tax Amount
$8.25
Sales Tax Guide
Free Online Sales Tax Calculator
Our free sales tax calculator helps you calculate the tax amount and final price of a purchase using a custom percentage rate. You can also reverse a tax-inclusive total to estimate the original pre-tax price and included tax amount.
The calculator supports custom tax percentages and multiple currency display options. It can be used for quick estimates involving purchases, invoices, products, services and general price calculations.
What Is Sales Tax?
Sales tax is generally calculated as a percentage of a taxable purchase price. The applicable rate can vary by jurisdiction, location, product type, service type and other rules. A calculator can perform the arithmetic, but the correct rate must still be determined for the relevant transaction.
How to Calculate Sales Tax
To calculate sales tax, convert the percentage rate to a decimal and multiply it by the pre-tax price. For example, an 8% rate becomes 0.08. If the pre-tax price is 100, the tax amount is 8 and the final tax-inclusive total is 108.
How to Add Sales Tax to a Price
Select Add Sales Tax mode, enter the original pre-tax price and provide the applicable tax rate. The calculator multiplies the price by the tax percentage and adds the resulting tax amount to the original price.
How to Remove Sales Tax from a Total
If a total price already includes sales tax, select Remove Sales Tax mode. Enter the tax-inclusive total and the applicable tax rate. The calculator divides the total by one plus the decimal tax rate to estimate the pre-tax amount.
What Is a Reverse Sales Tax Calculator?
A reverse sales tax calculator starts with a final tax-inclusive total and works backward to estimate the original price before tax. It also calculates the amount of tax included in the final total.
Sales Tax Rate vs Tax Amount
The sales tax rate is the percentage used in the calculation, while the tax amount is the monetary value produced by applying that percentage to the taxable price. For example, 8% is a rate, while $8 of tax on a $100 taxable price is a tax amount.
Why Sales Tax Rates Can Differ
Tax rules can differ across countries, states, provinces, cities and other jurisdictions. Rates may also vary according to the type of product or service and whether an exemption applies. Always verify the applicable rate with an authoritative source when accuracy is important.
Sales Tax Calculator for Business Estimates
Businesses can use a sales tax calculator for quick arithmetic checks involving estimated prices, quotations and internal calculations. However, actual tax collection, reporting and compliance may involve jurisdiction-specific rules that are not captured by a simple percentage calculator.
Sales Tax Calculator for Online Shopping
When you know an estimated tax rate, the calculator can help estimate the final cost of a purchase. Actual checkout tax may differ because sellers can apply location-specific rules, exemptions, product classifications and other requirements.
Important Tax Disclaimer
This calculator performs general mathematical estimates only. It does not determine whether a transaction is taxable, identify the legally correct tax rate or provide tax, accounting or legal advice. Tax rules and rates can vary by jurisdiction and transaction type. Verify applicable requirements with an official tax authority or qualified professional when needed.
FAQ
Frequently Asked Questions
Multiply the pre-tax price by the sales tax
rate divided by 100. Add the resulting tax
amount to the original price to find the total.
Divide the tax-inclusive total by one plus
the tax rate expressed as a decimal. Subtract
the resulting pre-tax price from the total
to estimate the included tax.
Yes. Enter any applicable percentage rate
supported by the calculator instead of using
one of the quick-rate buttons.
No. You provide the rate manually. This is
useful because applicable tax rules can vary
by jurisdiction, transaction and product or
service type.
It starts with a tax-inclusive total and
estimates the original pre-tax amount and
the tax included in that total.
Yes. The calculator is available as a free
online tool for general mathematical estimates.