How to use Sales Tax Calculator
- Choose Add tax to a price or Find the tax inside a price.
- Enter the amount and the tax rate that applies to your purchase; check that rate with your local tax authority.
- Choose the displayed rounding. The base price, tax and total update as you change the fields.
Example: Sales Tax Calculator
Add an illustrative 8.25% rate to a 100.00 pre-tax price.
Options
- Add or extract
- Add multiplies the pre-tax amount by the rate, then adds tax. Extract starts with a tax-included total and divides by one plus the rate to find the base price.
- Tax rate
- Type the rate as a percentage, such as 8.25, after confirming the rate and taxable status that apply. The tool has no location or product lookup.
- Rounding
- Choose two decimals for cents or whole amounts for a coarse display. Tax authorities and sellers may apply different rounding rules across items or invoices.
Supported inputs and limits
Where your input is processed
This tool processes your input in this browser. Your text and files are not uploaded to UseFreeTools. Check this tool's limits for anything it may save on your device.
Sources and assumptions
Checked 2026-09-26. The rate is always the one you enter; the tool does not infer one from your location. The example rate of 8.25% is illustrative, not a claim about any place. The formula assumes one uniform percentage on the entered amount: added tax = price times rate; included tax = total minus total divided by (1 + rate). New York State's tax department provides current rate lookup guidance, showing why a real transaction needs a location-specific check. This arithmetic aid is not tax or legal advice.
New York State Department of Taxation and Finance, Find sales tax rates (checked 2026-09-26)
Questions about Sales Tax Calculator
Where does the tax rate come from?
You enter it. The calculator does not infer a rate from your location or the amount. Check the current rule for the sale, including any local component or exemption.
How do I find tax already included in a price?
Select Find the tax inside a price and enter the full tax-included amount. The tool divides that amount by one plus your rate, then shows the base price and the difference as tax.
Why might a receipt differ by a cent?
A seller may round tax on each item, while a simple calculator rounds once on the total. Product exemptions or a different applied rate can also change the receipt.