🧮Sales Tax Calculator
Calculate sales tax on any purchase. Find the tax amount, total price, and per-item tax for single or multiple-quantity purchases.
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Total Price (with Tax)
$108.00
Tax (8.0%): $8.00. Total: $108.00.
Price Breakdown
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Sales Tax Calculator: How to Calculate Sales Tax on Any Purchase
A sales tax calculator adds the applicable tax percentage to a purchase price to show the final amount you pay at checkout. It also works in reverse — enter the final price to find the original pre-tax amount. US sales tax is collected at the state and local level, so combined rates range from 0% (in states like Oregon) to over 10% in some localities.
Formula: Total = Price × (1 + Tax Rate ÷ 100) | Tax Amount = Price × Tax Rate ÷ 100
| Variable | Example | Description |
|---|---|---|
| Purchase price | $85.00 | Pre-tax price |
| Sales tax rate | 8.25% | State + local combined rate |
| Tax amount | $7.01 | $85 × 8.25% |
| Total at checkout | $92.01 | Final price including tax |
Sales tax is one of the most common calculations in everyday financial life, yet it catches many people off guard at checkout. This sales tax calculator lets you find the total price with tax added, calculate the tax amount on any purchase, or work backwards to find the original price before tax. Sales tax in the United States is collected at the state and local level — there is no federal sales tax — creating a wide range of combined rates depending on exactly where you shop.
How to Calculate Sales Tax
The formula for adding sales tax to a price is: Total Price = Net Price × (1 + Tax Rate)
Example: an item costs $120 and the combined sales tax rate is 8.5%.
- Tax amount: $120 × 0.085 = $10.20
- Total with tax: $120 + $10.20 = $130.20
- Or in one step: $120 × 1.085 = $130.20
For a shopping cart with multiple items, add up all the taxable item prices to get the subtotal, then multiply the subtotal by (1 + tax rate) to get the total with tax. Non-taxable items (groceries, prescriptions) should be excluded from the taxable subtotal before applying the rate.
Reverse Sales Tax: Finding the Pre-Tax Price
If you know what you paid (tax included) and need to find the original net price, use the reverse formula: Net Price = Total Paid ÷ (1 + Tax Rate)
Example: you paid $86.40 total and the tax rate is 8%.
- Net price: $86.40 ÷ 1.08 = $80.00
- Tax amount: $86.40 − $80.00 = $6.40
A common mistake is multiplying the total by the tax rate (e.g., $86.40 × 0.08 = $6.91) — this is incorrect because it applies the tax rate to a price that already includes tax, producing an inflated figure. The correct method always divides by (1 + rate). The error compounds significantly on large purchases or in business accounting where accurate tax amounts must be recorded separately.
Sales Tax Rates by State
The US has no federal sales tax, but 45 states and the District of Columbia levy a state-level sales tax. Five states charge no state sales tax: Alaska, Delaware, Montana, New Hampshire, and Oregon. However, Alaska allows local jurisdictions to impose their own sales taxes, so some Alaskan municipalities do have a local rate.
Local counties, cities, and special districts can add tax on top of the state rate. The combined rate is what actually applies to your purchase. Notable combined averages for 2024–2025:
- Tennessee: ~9.6% average combined (highest in the nation)
- Louisiana: ~9.5% average combined
- Arkansas: ~9.5% average combined
- Washington: ~9.4% average combined
- Alabama: ~9.2% average combined
- California: ~8.7% average combined (statewide rate 7.25%; some cities reach 10.75%)
- Illinois: ~8.8% average combined
- New York: ~8.5% average combined
- Texas: ~8.2% average combined
- Florida: ~7.0% average combined
- Colorado: ~7.8% average combined (lowest state rate at 2.9%)
These are averages; the rate for your specific address may differ. Check your state Department of Revenue website for an address-level lookup tool to find the exact combined rate for any location.
What Is and Is Not Subject to Sales Tax
Not every purchase is taxable. Exemptions vary significantly by state but follow these general patterns:
- Commonly exempt in most states: Unprepared grocery food, prescription medications, and in some states, certain clothing items under a dollar threshold
- Almost always taxable: Restaurant meals (prepared food), electronics, furniture, vehicles, digital downloads, and most household goods
- Varies by state: Candy and soft drinks (some states tax them as food, others don't), over-the-counter medications, dietary supplements, and agricultural supplies
- Services: Traditionally exempt in most states, but an increasing number of states now tax certain services including software-as-a-service (SaaS), streaming subscriptions, and professional services
When budgeting for a large purchase, always verify the taxability of the specific item in your jurisdiction, as the exemptions are often more detailed than the general categories suggest.
Sales Tax vs. Use Tax
Sales tax is collected by the seller at the point of sale. Use tax is its complement — a tax owed by the buyer on taxable items purchased without sales tax. If you buy an item from an out-of-state online retailer that does not collect your state's sales tax, you technically owe use tax on that purchase at your state's rate. Use tax is self-reported on state income tax returns. Enforcement is limited for individual consumers, but it is a legal obligation in all states that have sales tax.
Since the Supreme Court's 2018 South Dakota v. Wayfair decision, most large online retailers are required to collect and remit sales tax in states where they meet economic nexus thresholds (typically $100,000 in sales or 200 transactions per year). This has significantly reduced the use-tax gap for purchases from major platforms like Amazon, but smaller online sellers may still not collect in every state.
Sales Tax for Business Owners and Sellers
If you sell taxable goods or services, you must:
- Register for a sales tax permit in every state where you have nexus — either physical (an office, warehouse, or employee in the state) or economic (exceeding the state's sales or transaction thresholds)
- Collect the correct combined rate at the point of sale based on the customer's delivery address (destination-based sourcing) in most states
- File and remit collected taxes on the state's required schedule (monthly, quarterly, or annually depending on your sales volume)
Multi-state sales tax compliance is complex. Tax automation platforms like TaxJar, Avalara, and Vertex integrate with e-commerce systems to calculate the correct rate for every transaction, handle filing, and manage nexus tracking automatically — essential for any business selling in multiple states.
Comparing Prices Across States: Tax-Inclusive Pricing
When comparing the true cost of a large purchase across different tax jurisdictions, always use the total tax-inclusive price rather than the listed price. A $50,000 vehicle purchased in a state with 9% combined sales tax costs $54,500 total, versus $50,000 in a state with no sales tax. For high-value items like vehicles, boats, and jewelry, researching sales tax rates before purchasing — and whether your state requires you to pay use tax if you buy elsewhere — can inform the decision of where to make the purchase.
Frequently Asked Questions
How do I calculate sales tax on a purchase?
Multiply the net price by the tax rate expressed as a decimal, then add to the original price. Example: $80 item at 8% sales tax → $80 × 0.08 = $6.40 tax → total $86.40. Shortcut: multiply the price directly by (1 + rate): $80 × 1.08 = $86.40. For multiple items, add all taxable item prices to get the subtotal, then multiply the subtotal by (1 + rate).
Which states have no sales tax?
Five states charge no state-level sales tax: Alaska, Delaware, Montana, New Hampshire, and Oregon. Alaska allows municipalities to charge local sales tax, so some Alaskan cities do have a rate. For large purchases, buying in a no-tax state can produce meaningful savings — but your home state may require you to self-report and pay use tax on items brought back across the border.
How do I calculate the original price before sales tax?
Use the reverse formula: Net Price = Total Paid ÷ (1 + Tax Rate). If you paid $109 with a 9% tax rate: $109 ÷ 1.09 = $100 pre-tax price; tax amount = $9. Avoid the common error of multiplying the total by the rate ($109 × 0.09 = $9.81) — this gives the wrong answer because you're applying the rate to a tax-inclusive price.
What is the average US sales tax rate?
The national average combined state and local rate is approximately 7–8%. Tennessee, Louisiana, Arkansas, and Washington have the highest combined averages at around 9.4–9.6%. California has the highest statewide base rate at 7.25%. Oregon, Montana, Delaware, and New Hampshire have no sales tax. Colorado has the lowest state rate at 2.9%, though local additions bring the combined average higher.
Are groceries subject to sales tax?
It depends on the state. Most states exempt unprepared grocery food from sales tax, but about a dozen states do tax groceries at either the full rate or a reduced rate. Prepared food (restaurant meals, hot foods at grocery delis) is taxable in virtually all states. Candy, soft drinks, and dietary supplements occupy a gray area — some states exempt them as food, others tax them as non-essential items. Check your specific state's rules for the items you buy regularly.
What is the difference between sales tax and use tax?
Sales tax is collected by the seller at the point of sale. Use tax is owed by the buyer on taxable items purchased without sales tax — most commonly, items bought from out-of-state online sellers that did not collect your state's rate. Use tax is reported on state income tax returns. Since the 2018 Wayfair Supreme Court ruling, most major online retailers collect sales tax in all states where they meet economic nexus thresholds, so the use tax obligation arises less often than it once did.