Sales Tax Calculator

The forward direction is straightforward: tax = price × rate, and total = price + tax. A $100 item at 8.25% carries $8.25 of tax and rings up at $108.25. The one-step version is quicker and less error-prone: multiply by 1 + rate. At 8.25% that is 100 × 1.0825 = $108.25 directly. At 6% it is × 1.06; at 9.5% it is × 1.095. That single multiplier is also what lets you answer the question people actually have in a store, which is how much a shelf price will really cost. A $34.99 item in a place with a 7% combined rate comes to 34.99 × 1.07 = $37.44. Knowing your own local multiplier by heart is genuinely useful — it turns every shelf price into an out-the-door price without a calculator.

This is the direction people get wrong, and it is worth understanding rather than memorizing. If a receipt says $108.25 including 8.25% tax, you cannot take 8.25% of $108.25. That gives $8.93, which is too much, because the tax was charged on the smaller pre-tax price and not on the total. The correct move is division: price before tax = total ÷ (1 + rate) So 108.25 ÷ 1.0825 = $100.00, and the tax was $8.25. Switch the mode field to run it this way. The size of the error is neat enough to be memorable: multiplying instead of dividing overstates the tax by exactly the rate again. At 8.25% you overstate by 8.25% ($8.93 versus $8.25). At 20% you overstate by 20%. The mistake grows with the rate, which is why it is nearly invisible at 4% and glaring on a European VAT receipt. This reverse calculation comes up more often than you would think: separating tax on a receipt for an expense report, working out a pre-tax price from an all-in quote, or checking whether a "tax included" price was computed correctly.

Whatever rate applies where the sale takes place — which is precisely why this calculator ships no rate table. In the US, sales tax is a state tax that is frequently stacked with county, city and special-district rates. The number you actually pay is the combined rate, and it can differ between two stores a few miles apart or even across a street that happens to be a jurisdiction boundary. A handful of states levy no statewide sales tax at all — Alaska, Delaware, Montana, New Hampshire and Oregon — though localities within Alaska impose their own. For deliveries and online orders, most states apply destination-based sourcing: the rate is the one where the buyer receives the goods, not where the seller sits. A few use origin-based rules for intrastate sales. This is the single most common reason an online total does not match what you expected. Rates also change, often at the start of a quarter or a fiscal year, and local add-ons come and go with voter-approved measures. Look up your current combined rate — the Tax Foundation and Streamlined Sales Tax references below are good starting points — and enter it here rather than trusting a number you memorized last year.

The rate is only half of the calculation. The other half is whether the item is taxable at all, and that varies enormously by state. Groceries are the biggest example: many states exempt unprepared food entirely, some tax it at a reduced rate, and a few tax it fully — while prepared food from the same store is usually taxable everywhere. Prescription drugs are widely exempt. Clothing is exempt in some states, exempt below a dollar threshold in others, and fully taxable elsewhere. Digital goods and services are treated inconsistently across the country and the rules are still moving. Several states run temporary sales tax holidays, typically around back-to-school season, suspending tax on specific categories for a few days. Some purchasers — resellers buying for inventory, certain nonprofits and government bodies — are exempt from tax on qualifying purchases when they provide the appropriate documentation. All of which means a single blended rate applied to an entire basket is an approximation. If a receipt shows less tax than you expected, an exempt item in the basket is the most likely explanation. This page is arithmetic, not tax guidance; check your state's revenue department or a qualified professional for how the rules apply to a specific transaction.

A few recurring traps, beyond multiplying when you should divide. Discounts. A store discount reduces the taxable price, and tax is charged on the reduced amount — so a discount trims the tax too. Manufacturer coupons are treated differently in some states, because the retailer is reimbursed for the coupon value, which can mean tax is computed before the coupon comes off. That is the usual explanation for a receipt that looks a dollar high. Shipping and handling. Whether delivery charges are taxable depends on the state and sometimes on whether shipping is stated separately from the goods. It is not safe to assume either way. Rounding. Tax computed line by line and then summed does not always equal tax computed once on the invoice total; the two can differ by a cent or two. Both approaches are used in practice, which is why a hand-checked receipt occasionally comes out a penny off. Tax on tax. Sales tax is charged on the price of goods, not on other taxes or on the tip. If you are reverse-engineering a restaurant check, take the tip out before dividing by 1 + rate, or the pre-tax figure will be wrong.