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Alaska has no state sales tax and, on the count of the commission its own municipalities set up to administer the local ones, over 100 separate taxing jurisdictions. A rate belongs to an address rather than to a state, which is why the field above asks you for one instead of guessing. What is published, and quoted below, is the rule that decides the half cent, and it is not the rule most people would assume.
Last updated 1 October 2026
An arithmetic helper, not tax advice. This page multiplies an amount by a rate you supply, or divides a tax-inclusive total by one plus that rate. The rate is yours to establish: every figure quoted below carries its source and the date it was read, and sales tax rates, exemptions and sourcing rules are changed by state legislatures and by town ordinance on no fixed schedule.
Illinois stopped charging its one per cent state grocery tax on 1 January 2026. Whether your groceries are taxed in Illinois today depends on whether your municipality or county passed an ordinance, because the same change “authorized municipalities and counties to impose a local grocery tax rate of exactly one-percent (1%) by ordinance.” Two shops a mile apart, same state, same till software, different answer.
That is the ordinary condition of a sales tax rate in the United States, not an oddity. Alaska makes it vivid. The Alaska Remote Seller Sales Tax Commission, which Alaskan municipalities created to administer their own taxes, states that “Alaska does not currently have a state sales tax, yet local governments have the authority to institute a local sales tax”, that “there are over 100 different taxing jurisdictions in Alaska”, and that “local governments maintain control over their designated sales tax rates and exemptions.” The Commission’s own solution is not a rate table. It is a mapping service that resolves “the sales tax rules for an individual delivery address in Alaska.”
At the other end, Oregon has nothing to resolve. Its Department of Revenue: “Oregon doesn’t have a general sales or use/transaction tax.”
In between, a rate is a stack. Florida’s Department of Revenue states that “Florida’s general state sales tax rate is 6%” and that “many Florida counties have a discretionary sales surtax (county tax) that applies to most transactions subject to the sales or use tax.” Texas caps the local part rather than the whole: its Comptroller writes that “the local tax due cannot be more than 2 percent, so the most tax you can collect is 8.25 percent.” No more than two of those eight and a quarter points may be local, and which local jurisdictions happen to cover a given address is a question about geography rather than about the state.
So the rate field above is not laziness. It is the only honest design for a page that does not ask where you are. Find the rate once, from the revenue department of your own state, and reuse it.
The Streamlined Sales and Use Tax Agreement, which its member states adopted to standardise questions exactly like this one, is the closest thing the subject has to a written standard. Its default answer is destination. Section 310 sets out an ordered test, and a seller works down it until one of the steps produces an address:
Sourcing a retail sale · Streamlined Sales and Use Tax Agreement, Section 310(A)
Step one is the one that catches people out. Walk into a shop and carry the goods away and the sale is sourced to the shop, whatever your own address is. Steps three and four are what an online seller falls back on when it has no delivery address, which is why a rate can be derived from the billing address on a card.
Then Section 310.1 lets a member state throw the middle of that list away. A state may elect to source an in-state sale “to the location where the order is received by the seller”, provided the order and the delivery are in the same state. Texas works on that principle: “In general, local sales tax is based on the seller’s place of business”, where a place of business is “a store, office or other location operated by the seller to sell taxable items where sales personnel receive three or more orders during the calendar year.” Orders that no salesperson handles are treated differently again: “orders not received by sales personnel are considered to be received at locations that are not places of business of the seller.”
One sentence in the origin election is worth reading twice, because it closes the obvious escape. Where a state sources to the seller’s location, “the purchaser shall not be entitled to any refund if the combined state and local rate or rates at the location where the product is received by the purchaser is lower than the rate where the order is received by the seller.” You can be charged a rate that does not exist where you live, correctly, with no claim to the difference.
A receipt rarely has one taxable base. Categories are carved out by statute, sometimes at a different rate, sometimes only up to a threshold, and sometimes only by the state while the county keeps charging.
New York’s clothing exemption is the cleanest illustration of all three at once. Tax Bulletin ST-122, issued 10 March 2014, says “clothing and footwear sold for less than $110 per item or pair and items used to make or repair this clothing are exempt from the New York State 4% sales and use taxes.” The threshold is per item, so a $400 coat is fully taxable while four $99 coats are not. And the exemption stops at the state line of the tax, not the state line of the map: it “does not apply to local sales and use taxes unless the county or city imposing the taxes elects to provide the exemption”, with the same election governing the three-eighths of one per cent Metropolitan Commuter Transportation District tax.
The $110 figure is not a coincidence. Section 323 of the Streamlined Agreement permits its members a clothing threshold and fixes a floor under it: “the threshold on the sales price or purchase price of each individual item of clothing may not be less than $110, and must apply to both the state and any local sales or use taxes.” Note what the member states agreed that New York did not: that the exemption travels down to the local taxes automatically.
Medicine is often exempt on a labelling test rather than a price test. Texas: “OTC drugs and medicines labeled with a Drug Facts panel in accordance with the regulations of the federal Food and Drug Administration (FDA) are exempt from sales tax”, and where a product is a medicine but carries no such label, “a physician must prescribe or dispense the drug or medicine for it to be exempt.” So the taxability of the thing in your hand can turn on which panel the manufacturer printed on the box.
The practical consequence for this page: feed it the taxable portion of a basket. A single multiplication over a mixed receipt is wrong by whatever the exempt items were worth, and no rate field can repair that.
Multiply almost any price by almost any rate and you get a third decimal place. What happens to it is not a convention, a preference or a floating-point accident. It is written down.
Florida: “Effective July 1, 2021, businesses that collect and remit sales and use taxes to the Florida Department of Revenue must use a rounding algorithm when calculating the sales tax due on a transaction. Using this algorithm, the computation of the tax must be carried to the third decimal place; if the third decimal place is greater than 4, the tax must be rounded up to the next cent.”
The Streamlined Agreement requires the identical algorithm of every member state, at Section 324: “tax computation must be carried to the third decimal place”, and “the tax must be rounded to a whole cent using a method that rounds up to the next cent whenever the third decimal place is greater than four.”
Two things fall out of that, and both are worth more than the rule itself.
The rule applied, in exact decimal arithmetic · the rates here are arithmetic inputs, not any jurisdiction’s current rate
First, the half cent always goes up, and it goes up every time rather than alternating. Rounding to even, which is what a statistician and several programming languages would do with 0.225, is not what the rule says. Second, the rule operates on the third decimal place rather than on the exact product, so a figure like $1.6741625 is cut to $1.674 before anything is decided, and 4 is not greater than 4.
Section 324 also settles something people argue about at the till. A seller may round the tax on each item or on the invoice total, because each member state must “allow sellers to elect to compute the tax due on a transaction on an item or an invoice basis”, and must let the rounding apply to “the aggregated state and local taxes.” Eight items rounded individually and one total rounded once are genuinely different sums. Two shops can charge you a cent apart for the same basket and both be complying.
And the method that preceded all this is gone by agreement: “no member state shall require a seller to collect tax based on a bracket system.” Florida’s own publication announcing the 2021 change is titled “Rounding to Replace ‘Bracket System’ in Calculation of Sales and Use Taxes”. If you have ever seen a laminated card by a register with a column of price ranges and a column of cents, that was a bracket table.
Going backwards from a tax-inclusive total is where confident arithmetic goes astray. A total is the pre-tax amount multiplied by one plus the rate, so the pre-tax amount is the total divided by one plus the rate. Subtracting the rate from the total is a different operation and gives a different answer.
$108.25 inclusive of 8.25% tax
The gap grows with the rate and with the total. At 10% on a $1,000 inclusive invoice the correct pre-tax figure is $909.09 and the shortcut gives $900.00, a $9.09 error. The Remove tax mode above divides.
Two figures go into the panel above: an amount and a rate. Everything below is something a pair of numbers cannot encode, and each one is a fact about the tax rather than about the page.
An address. A rate is a state rate plus whatever local taxes cover one point on a map, and in Alaska it is local ordinances with no state layer underneath at all. Over 100 jurisdictions in that one state set their own rates and exemptions. The rate you type is a conclusion somebody else reached about a location.
Which address the law cares about. Destination under Section 310, origin under the Section 310.1 election, the seller’s place of business in Texas. A rate on its own does not say which rule produced it, and under an origin rule the correct rate may be one that applies nowhere near you.
What is being bought. Groceries, prescription and over-the-counter medicine, clothing under a threshold, and in many states services are all treated separately, by statute, per state, and in Illinois since 1 January 2026 per municipality. One rate over a mixed basket is one rate over the wrong base.
A threshold. New York’s clothing exemption applies per item, under $110, to the state tax and only to those local taxes whose county or city elected it. A percentage has no concept of a per-item ceiling.
Which rounding election the seller made. Item basis or invoice basis, both permitted by Section 324, and they disagree by a cent or two on a long receipt.
Anything about freight, installation, returns, resale certificates or use tax. None of those is a field here, and each has its own body of state rules.
Today’s rate. Every figure on this page is dated and sourced because every one of them is subject to change by a legislature or a town council. The Illinois grocery change took effect nine months before this revision. Treat an old rate the way you would treat an old timetable.
Boundary behaviour worth knowing. Unlike the other money pages here, this one refuses input it cannot use rather than quietly substituting a figure: a negative amount or rate, an amount above $1 trillion, or a rate above 100% produces a message and no result. The trillion is where whole cents stop being exact arithmetic here, not a view about prices.
Nothing you type into the fields above leaves your browser.
Every quotation above was read from the page or document named on 1 October 2026. The decimal arithmetic in the rounding table was carried out by hand to the exact figure before any rounding rule was applied. Part of the QuikUtil tools collection; the Discount Calculator handles the order a discount and a tax are applied in, and the Percentage Calculator is the same arithmetic without the tax vocabulary.
Because a rate is a property of an address, not of a state, and this page has two numbers to work from. Alaska is the clearest case: the Alaska Remote Seller Sales Tax Commission, set up by Alaskan municipalities to administer their taxes, says “Alaska does not currently have a state sales tax, yet local governments have the authority to institute a local sales tax”, that “there are over 100 different taxing jurisdictions in Alaska”, and that “local governments maintain control over their designated sales tax rates and exemptions”. Its own answer to the problem is a mapping service that resolves “the sales tax rules for an individual delivery address in Alaska”. A single field cannot do that, so it asks you for the answer rather than guessing it.
Oregon. Its Department of Revenue states it plainly: “Oregon doesn’t have a general sales or use/transaction tax.” Alaska has no state sales tax either, but over 100 local jurisdictions levy their own, so the honest answer there is that it depends entirely on the address. Enter 0 and this page will return the amount unchanged.
It rounds up, and that is written down rather than conventional. Florida requires that “the computation of the tax must be carried to the third decimal place; if the third decimal place is greater than 4, the tax must be rounded up to the next cent.” The Streamlined Sales and Use Tax Agreement imposes the same algorithm on its member states at Section 324. So $5.00 at 4.5% is exactly $0.225 of tax, the third decimal is a 5, and the tax is $0.23, not $0.22. On $19.99 at 8.375% the exact figure is $1.6741625, the third decimal is a 4, and the tax is $1.67.
Yes, and the Agreement says so. Section 324 requires each member state to “allow sellers to elect to compute the tax due on a transaction on an item or an invoice basis”. Rounding eight items separately and rounding their total once are different sums, and a seller is entitled to either. The same section also forbids a state from requiring the old bracket method: “No member state shall require a seller to collect tax based on a bracket system.” Florida used brackets until 1 July 2021 and replaced them with the rounding algorithm above.
Usually yours, sometimes theirs, and the difference is a deliberate state choice. The Streamlined Agreement’s default at Section 310 is destination: “When the product is not received by the purchaser at a business location of the seller, the sale is sourced to the location where receipt by the purchaser ... occurs”. Section 310.1 then lets a state elect origin instead, sourcing a sale “to the location where the order is received by the seller” for in-state sales. Texas works that way: its Comptroller says “In general, local sales tax is based on the seller’s place of business.” Under the origin election you also have no claim to the difference: “The purchaser shall not be entitled to any refund if the combined state and local rate or rates at the location where the product is received by the purchaser is lower than the rate where the order is received by the seller.”
Frequently not, and the exceptions are specific to a state and sometimes to a town. Texas exempts over-the-counter medicine outright where it carries a federal label: “OTC drugs and medicines labeled with a Drug Facts panel in accordance with the regulations of the federal Food and Drug Administration (FDA) are exempt from sales tax.” New York exempts “clothing and footwear sold for less than $110 per item or pair” from its 4% state tax, but the exemption “does not apply to local sales and use taxes unless the county or city imposing the taxes elects to provide the exemption”. Illinois ended its 1% state grocery tax on 1 January 2026 and in the same change “authorized municipalities and counties to impose a local grocery tax rate of exactly one-percent (1%) by ordinance”. Run the taxable part of a basket through this page, not the whole receipt.
It divides rather than subtracting. A tax-inclusive total is the pre-tax amount multiplied by one plus the rate, so recovering the pre-tax amount means dividing by that same figure. $108.25 at 8.25% comes back to $100.00, because 108.25 divided by 1.0825 is 100. Subtracting 8.25% of $108.25 would give $99.32, which is the most common mistake on this calculation and is wrong by 68 cents.
No. It is a multiplication and a division, with the rules behind the rounding named and dated. It does not know your address, what you are buying, who is selling it or which state’s sourcing rule governs the sale. Rates and exemptions change on ordinary legislative timetables, and the Illinois grocery change above took effect nine months before this page was last revised. Confirm anything that matters with the revenue department of the state you are in.