Sales Tax Calculator
Add sales tax to a price or break the tax amount out of a tax-inclusive total.
Set your values
Adjust the values, then calculate your result.
How to use Sales Tax Calculator
- Enter the measurements or amounts in the fields above.
- Check that dimensions, rates and units match the labels.
- Select “Calculate sales tax” to see a clear estimate and the formula used.
How the sales tax calculator works
For a pre-tax price, tax = amount × rate and total = amount + tax. For a tax-inclusive total, pre-tax amount = total ÷ (1 + rate) and tax is the difference.
Check your measurements and assumptions
The calculator handles one flat rate. Tax rules, exemptions, rounding and combined local rates vary by location; confirm the applicable rate with your tax authority.
Review the estimate before you act
Compare this result with an independent measurement, supplier quote or institution guidance when the decision matters. Confirm that the units and assumptions match the labels above, and update the inputs when the conditions change. Keep a note of the values used so you can reproduce the estimate later. This calculator is a planning aid and does not replace professional, product-specific or local guidance.
How do I remove sales tax from a total?
Divide the tax-inclusive amount by one plus the tax rate as a decimal. Subtract that pre-tax amount from the total to find tax paid.
Is input uploaded?
Processing takes place in your browser. This tool does not send your input or selected files to a conversion API.