Sales Tax Calculator
Sales tax in the United States is set at the state and local level, so the rate on the same purchase can swing from 0% (Delaware, Oregon, Montana, New Hampshire) to over 10% in parts of Louisiana, Tennessee, and California. This calculator works both ways: enter a pre-tax price to add tax, or enter a receipt total to reverse-engineer the tax already baked in.
When to use this calculator
- Adding state and local sales tax to a price before checkout
- Reverse-calculating the tax already included in a receipt total
- Comparing the out-the-door cost of a purchase across states with different rates
- Separating pre-tax revenue from collected tax for bookkeeping
- Estimating tax on a big-ticket item (appliance, furniture, electronics)
- Checking whether a quoted 'tax included' price matches the advertised rate
How it works
2 min readWhat is a sales tax calculator?
A sales tax calculator computes the tax owed on a purchase from a price and a tax rate. It runs in two directions: forward (add tax to a pre-tax price to get the total) or reverse (extract the tax portion from a tax-inclusive total). In the US, sales tax is a combined state + county + city + special-district rate, which is why two stores a few miles apart can charge different amounts.
How It Works
You provide an amount and a rate, then choose whether the amount is pre-tax (add mode) or tax-inclusive (reverse mode). In add mode the tax is a simple percentage of the price. In reverse mode the calculator divides the total by 1 + rate to recover the original pre-tax price, then takes the difference as tax.
Formula
r = rate / 100
// Add mode (amount is pre-tax)
tax = amount * r
total = amount + tax
net = amount
// Reverse mode (amount is tax-inclusive total)
net = amount / (1 + r)
tax = amount - net
total = amountWorked Example
Add mode: $100.00 at 8.25%.
| Step | Value |
|---|---|
| Rate as decimal | 0.0825 |
| Tax = 100 × 0.0825 | $8.25 |
| Total = 100 + 8.25 | $108.25 |
Reverse mode: a receipt total of $108.25 at 8.25%.
| Step | Value |
|---|---|
| Pre-tax = 108.25 ÷ 1.0825 | $100.00 |
| Tax = 108.25 − 100.00 | $8.25 |
Example Combined Rates (2026)
| State | Typical combined rate |
|---|---|
| Oregon, Delaware, Montana, New Hampshire | 0% (no state sales tax) |
| California | 7.25%–10.75% |
| Texas | 6.25%–8.25% |
| New York | 4%–8.875% |
| Louisiana | up to ~11.45% |
Limitations
Frequently asked questions
How do I calculate sales tax on a price?
Multiply the pre-tax price by the tax rate expressed as a decimal. For an 8.25% rate, multiply by 0.0825. Example: $100 × 0.0825 = $8.25 tax, for a total of $108.25. This calculator does it automatically in 'add' mode.
How do I reverse sales tax out of a total?
Divide the tax-inclusive total by (1 + rate). For a $108.25 total at 8.25%: $108.25 ÷ 1.0825 = $100.00 pre-tax, so the tax was $8.25. Use the 'reverse' mode to do this automatically — it's the correct method (subtracting 8.25% from the total would be wrong).
Which US states have no sales tax?
Five states have no statewide sales tax: Oregon, Delaware, Montana, New Hampshire, and Alaska (though Alaska allows local sales taxes). In these states, the listed price is the price you pay, aside from any local levies.
What is the difference between sales tax and VAT?
Sales tax (US) is charged once, at the final retail sale, and is added on top of the price. VAT/GST (most of the world) is collected at each stage of production and is usually already included in the displayed price. The math differs — use a VAT calculator for value-added tax.
Is sales tax based on where I buy or where I live?
Generally it's based on the point of sale or the delivery destination (destination-based sourcing) for most states. For online purchases, the rate is typically the buyer's shipping address. Origin-based states (like Texas for in-state sellers) use the seller's location.
Why is the combined rate higher than the state rate?
Most states let counties, cities, and special districts add their own local sales taxes on top of the state rate. So a 6.25% state rate can become 8.25% or more once city and county taxes are layered in. Always check the combined rate for the specific location.
Are groceries and medicine taxed?
It varies by state. Many states exempt groceries and prescription drugs entirely or tax them at a reduced rate. Some tax prepared food differently from raw groceries. This calculator applies one flat rate, so adjust the rate if your category is exempt or reduced.
Do I charge sales tax as a small business?
If you have nexus (a physical or economic presence) in a state that levies sales tax and sell taxable goods or services there, you generally must collect and remit it. Economic nexus thresholds (e.g., $100,000 in sales) apply to remote sellers after the 2018 Wayfair ruling. Consult your state's Department of Revenue.
Does this calculator include local and city taxes?
It applies whatever single rate you enter. To include local and city taxes, enter the full combined rate for the location (state + county + city + district). You can look this up by ZIP code on your state's revenue website or a rate-lookup tool.