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Add sales tax to any price or pull the tax back out of a total. Our free sales tax calculator works with any rate — state, local, or combined.
Choose "add tax" or "extract tax," enter the price and tax rate. Adding multiplies the price by (1 + rate); extracting divides the total by (1 + rate) to recover the pre-tax price.
Formula: Total = Price × (1 + rate); Pre-tax price = Total ÷ (1 + rate); Tax = Total − Pre-tax price.
This calculator figures the sales tax on any purchase and the total you will pay at checkout — or works backward from a tax-included total to reveal the pre-tax price. It takes seconds.
Pro tip: For multi-item carts, add up all taxable items first and run the total once — the calculator’s math is identical to taxing each item separately (before rounding). But if some items are exempt (groceries, clothing in certain states), total only the taxable ones, as the multi-item example below demonstrates.
Sales tax is a consumption tax levied by state and local governments on the sale of goods and certain services. Unlike income tax, which is based on what you earn, sales tax is based on what you spend — and unlike the VAT used in most other countries, it is added at the register rather than baked into the sticker price, which is why Americans experience checkout totals higher than shelf prices.
There is no federal sales tax in the United States. Instead, 45 states plus thousands of local jurisdictions set their own rates, which combine into a single combined rate at the point of sale. A state rate of 6 percent might become 8.25 percent after county, city, and transit district additions. This layering is the number one reason people under-estimate their tax: they look up the state rate and miss the local add-ons that can contribute 2 to 4 percentage points.
Whether tax applies at all depends on nexus (the seller’s legal connection to your state) and the taxable base (which categories your state taxes). Since the 2018 South Dakota v. Wayfair Supreme Court decision, states can require out-of-state sellers with sufficient sales (economic nexus) to collect tax — so the old “no tax online” assumption is largely dead. Common exemptions include groceries (exempt or reduced in most states), prescription drugs, clothing under a threshold (New York exempts clothing under $110 per item), and purchases for resale by businesses holding a resale certificate.
Related concepts worth knowing: use tax is the tax you legally owe when a seller does not collect it (for example, buying from a small out-of-state vendor); tax holidays are limited periods when states suspend tax on categories like school supplies or clothing; and excise taxes are separate per-unit taxes on items like gasoline, tobacco, and alcohol that stack on top of sales tax. The calculator above handles the core computation — price times rate — that underlies every one of these situations.
All sales tax math reduces to three formulas:
Sales tax = Price × Tax rate
Total with tax = Price × (1 + Tax rate)
Pre-tax price = Total ÷ (1 + Tax rate)
Convert the percentage to a decimal first: 8.25 percent becomes 0.0825. Let us work through two complete examples.
Sales tax = $250 × 0.0825 = $20.625, which rounds to $20.63. Total = $250 × 1.0825 = $270.625, rounded to $270.63 — exactly what the calculator shows. Note the rounding: the true tax is $20.625, and standard half-up rounding gives $20.63. On a single purchase this penny is trivial; across a retailer’s millions of transactions, rounding rules are set by state regulation.
Forward: tax = $1,299 × 0.095 = $123.405 → $123.41; total = $1,299 × 1.095 = $1,422.405 → $1,422.41. Reverse: a receipt shows $1,422.41 with 9.5% tax included. Pre-tax price = $1,422.41 ÷ 1.095 = $1,299.00, and the embedded tax is $1,422.41 − $1,299.00 = $123.41. The reverse formula is invaluable for expense reports, business deductions, and checking whether a “tax included” price was computed honestly.
The pattern to internalize: multiplying by (1 + rate) adds tax; dividing by (1 + rate) removes it. Every tax question you will ever meet is one of these two operations.
Lena’s cart holds a $45 shirt, $120 shoes, and $30 of groceries. Her local rate is 7 percent, but her state exempts groceries from sales tax. What does she pay?
First, separate taxable from exempt items. Taxable subtotal = $45 + $120 = $165. Groceries ($30) are exempt and skip the tax computation entirely. Tax = $165 × 0.07 = $11.55. Total = $45 + $120 + $30 + $11.55 = $206.55.
Compare the common error: taxing the whole $195 cart gives $195 × 0.07 = $13.65, overpaying by $2.10. Small on one trip, but a household spending $400 monthly on groceries in an exempt state would overpay $28 every month — $336 per year — if it taxed everything. The calculator handles this correctly when you enter only the taxable subtotal ($165) as the price.
The business version of this example is bigger. A restaurant buying $2,000 of ingredients (exempt as manufacturing inputs in many states) alongside $500 of taxable supplies at 8 percent owes tax only on the $500: $40, not $200. Knowing which lines on an invoice are taxable routinely saves businesses hundreds per order, which is why exemption certificates and proper invoice coding matter.
Not everyone pays the sticker rate. Consider two shoppers legally paying less than the posted tax.
The resale exemption: David runs a boutique and buys $5,000 of inventory wholesale in a state with an 8 percent combined rate. Because the goods are for resale, he presents his resale certificate and pays $0 in sales tax instead of $400. The tax will be collected later from his retail customers on the final sale price. This is the single largest legal sales-tax saving most people will ever see — $400 on one purchase order — and it exists in every state with a sales tax. The catch: misuse of a resale certificate for personal purchases is tax fraud with real penalties.
The tax holiday: Maria’s state runs a back-to-school tax holiday weekend exempting clothing and school supplies. She times $600 of qualifying purchases to the holiday and saves $600 × 0.07 = $42. Combined with back-to-school sales, the holiday stacking is deliberate policy: states forgo revenue to concentrate shopping locally. Seventeen states typically offer some form of tax holiday each year, most in late summer.
The lesson: the posted rate is the starting point, not always the final word. Exemptions for resale, manufacturing, nonprofits, and holiday windows are written into every state’s code — check your state’s department of revenue site before any large purchase to see which apply to you.
1. Applying tax before the discount. A $100 item at 20 percent off with 8 percent tax costs ($100 − $20) × 1.08 = $86.40, not $100 × 1.08 − $20 = $88.00. Sales tax applies to the final sale price after discounts in nearly every state. On big-ticket items the order of operations matters: a $2,000 appliance at 15 percent off saves an extra $24 in tax when computed correctly.
2. Using the state rate and forgetting local add-ons. A 6 percent state rate with 2.25 percent in county and city taxes is really 8.25 percent — a 37.5 percent higher tax bill than expected. Always use the combined rate for the delivery ZIP code; the calculator’s rate field expects this total.
3. Assuming online purchases escape tax. Post-Wayfair, major retailers collect tax in every state with a sales tax, and marketplace facilitator laws extend this to third-party sellers on large platforms. If a small seller does not collect, you technically owe use tax on the purchase — states are increasingly enforcing this on income tax returns.
4. Ignoring rounding on large purchases. Each line item rounds to the cent, and states specify whether rounding happens per item or per invoice. On a $50,000 equipment purchase at 8.25 percent, the tax is $4,125.00 exactly — but per-line rounding across hundreds of SKUs can drift the total by dollars. For business purchases, reconcile the invoice’s tax line against your own computation.
5. Not tracking sales tax for deductions. Itemizers can deduct state and local sales tax instead of state income tax (subject to the $10,000 SALT cap) — valuable in states with no income tax like Texas or Florida. The IRS provides optional sales tax tables, but actual receipts usually yield a bigger deduction for large purchases like vehicles. Keep receipts; the deduction is only as good as your records.
Sales tax rarely travels alone. Our Discount Calculator computes sale prices before tax is applied, our Income Tax Calculator estimates the income tax that dwarfs most shoppers’ sales tax bills, and our Budget Calculator folds both into a monthly plan. Browse the full Financial Calculators collection for more.
This page provides a sales tax calculator with two modes: add tax to price, and extract tax from a tax-included total. Inputs: item price, tax rate (percent). Outputs: sales tax amount, total with tax (add mode) or pre-tax price and embedded tax (extract mode). Core formulas: tax = price × rate; total = price × (1+rate); pre-tax = total ÷ (1+rate). Default example: $250 at 8.25% → $20.63 tax, $270.63 total. The article explains U.S. sales tax structure (no federal tax; combined state+local rates; nexus; Wayfair economic nexus; use tax; exemptions; tax holidays), two worked formula examples ($250 at 8.25%; $1,299 laptop at 9.5% forward and reverse), a multi-item worked example ($45 shirt + $120 shoes taxable + $30 exempt groceries at 7% → $206.55), an exemption worked example ($5,000 resale purchase saves $400; $600 tax-holiday purchase saves $42), five common mistakes, and related calculators.
$250 × 8.25% = $20.63 tax, so the total is $270.63. The sales tax calculator above handles any rate instantly.
Divide by (1 + rate): a $270.63 total at 8.25% was $270.63 ÷ 1.0825 = $250.00 before tax.
There’s no federal sales tax; combined state + local rates average around 7–8%, ranging from 0% to over 10% in some cities.
Alaska, Delaware, Montana, New Hampshire and Oregon have no statewide sales tax (Alaska allows local taxes).
Generally yes — tax applies to the final sale price after discounts, which is why our discount calculator applies tax after the discount.
Multiply the price by the rate as a decimal: $100 × 0.08 = $8.00 in tax, for a $108.00 total. The general formula is tax = price × rate and total = price × (1 + rate). At the default example of $250 and 8.25%, the tax is $20.63 and the total is $270.63.
Usually yes. Since the 2018 Wayfair Supreme Court decision, states can require sellers with enough sales (economic nexus) to collect tax, and all major retailers now collect in every state with a sales tax. Marketplace facilitator laws extend this to third-party sellers on large platforms. If a small seller does not collect, you technically owe use tax on the purchase.
It varies by state, but common exemptions include unprepared groceries (most states), prescription drugs, and clothing under a price threshold — New York exempts clothing items under $110. Businesses buying for resale present a resale certificate and pay no tax on inventory. Many states also run annual tax holidays suspending tax on school supplies or clothing. Check your state’s department of revenue site for the full list.
Sources: figures use the standard tax formulas shown above and are cross-checked in the calculator; for official state rates and exemption rules, see your state’s department of revenue and the Streamlined Sales Tax Governing Board at streamlinedsalestax.org.
Also try our Discount Calculator, Income Tax Calculator and Budget Calculator for more money math, or browse all Financial Calculators.