Sales Tax Calculator
Two directions: price plus tax for the checkout total, or a receipt total split back into price and tax.
Sales tax turns clean prices into awkward totals — $100 becomes $108.75 in much of California — and the reverse question is just as common: a receipt shows only the total, and your expense report wants the pre-tax amount. This calculator works both directions: add tax to a price to see the tax amount and final total, or back out tax from a tax-included total to recover the original price.
The reverse direction trips people up because the intuitive move is wrong: you can't subtract 8.75% from the total, because the tax was computed on the smaller pre-tax number. The correct math divides by 1.0875 — which this calculator does — and the difference matters on anything bigger than lunch. US rates combine state, county and city portions, so the right rate is what your receipt or your city's finance page says, anywhere from 0% (Oregon, Montana, New Hampshire, Delaware) to over 10% in parts of Louisiana and Washington. If a discount is involved too, the discount calculator chains percent-off and tax in the order stores actually apply them.
How to use the Sales Tax Calculator
- Choose the direction: add tax to a price, or back tax out of a total.
- Enter the amount — the pre-tax price in add mode, the tax-included total in reverse mode.
- Enter your combined local tax rate (the percentage from a local receipt is the most reliable source).
- Read the pre-tax amount, the tax, and the total.
Frequently asked questions
How do I remove sales tax from a total correctly?
Divide the total by (1 + rate). A $108.75 total at 8.75% is 108.75 ÷ 1.0875 = $100.00 pre-tax. Subtracting 8.75% of the total instead gives $99.23 — wrong, because the tax was 8.75% of the price, not of the total.
What sales tax rate should I enter?
Your combined rate: state + county + city (+ special districts). The easiest source is any recent local receipt — divide the tax line by the subtotal. City finance websites and state revenue departments publish exact rates by address.
Why did I pay a different rate across town?
US sales tax is layered — a city or district line can add a point or more within the same county. Online orders are generally taxed at the delivery address's rate, so your rate can even vary between home and work deliveries.
Which states have no sales tax?
Oregon, Montana, New Hampshire and Delaware have no state or local sales tax; Alaska has no state tax but some localities charge their own. At the other end, combined rates top 10% in parts of Louisiana, Washington and Alabama.
Does this work for VAT or GST countries?
The math is identical — enter the VAT/GST rate. One difference in daily life: VAT countries display tax-included prices, so the "back out tax" mode is the one you'll use to see the net amount on invoices and expense claims.