Free Online Sales Tax Calculator
Add or remove sales tax and see the tax breakdown.
When you remove tax, the price you enter is treated as the tax-inclusive total. The net price is found by dividing the total by one plus the rate, so the tax amount is always calculated on the pre-tax value rather than on the gross amount.
About the Sales Tax Calculator
Sales tax is charged on the value of a taxable good or service and collected by the seller on behalf of a government authority. The rate depends on where the sale takes place, what is being sold, and sometimes who is buying. Because listed prices in many countries already include tax, a useful calculator has to work in both directions: adding tax to a net figure and extracting the tax that is buried inside a gross figure. This tool handles both modes and shows the net amount, the tax amount, and the final total at the same time.
Adding tax to a price
In add mode, the number you enter is the pre-tax price. The tax is calculated by multiplying that price by the rate divided by one hundred, and the total is the price plus the tax. For example, a net price of 1,000 at 8.25% produces 82.50 of tax and a total of 1,082.50. This is the mode to use when you are quoting a price to a customer, preparing an invoice, or checking the amount that should be collected at the point of sale.
Removing tax from a price
In remove mode, the number you enter is the tax-inclusive total. Dividing by one plus the rate extracts the net price, and the difference between the total and the net price is the tax. The common mistake is to subtract the rate from the total instead of dividing by the rate factor. At 10%, a gross price of 110 contains 100 of net value and 10 of tax, not 99 and 11. The calculator performs the correct division and displays the exact split, which is useful for expense reports, refunds, and reconciling receipts.
Rates, rounding, and local rules
The six preset buttons are short cuts for frequently used rates, but the rate field accepts decimals so you can enter a combined state, county, and city rate such as 8.875%. Results are rounded for display to two decimal places using standard currency formatting. Real tax jurisdictions may have their own rounding rules, exemptions, thresholds, and rules for shipping or services. The tool is an estimating aid, not a tax filing system; confirm the applicable treatment with the relevant tax authority or your accountant.
Frequently asked questions
Why is the tax in remove mode not simply the rate times the total?
Because the total already includes tax. The tax was calculated on the smaller net amount, so you must first divide the total by one plus the rate to recover the net value.
Can I use a rate with three decimal places?
Yes. The rate field accepts values such as 8.875, which is common when several local rates are combined.
Does the calculator round the tax the way a specific jurisdiction does?
It uses standard half-up display rounding at two decimal places. Some jurisdictions round per item or use different rules, so the final filed amount may differ by a cent.