Sales Tax Calculator
What this calculator does
This calculator computes the sales tax amount and total price for a purchase given the item price and applicable tax rate. It can also work in reverse—calculating the pre-tax price from a tax-inclusive total. This is useful for budgeting, price comparisons, and understanding the true cost of purchases.
Sales tax in the United States is a consumption tax imposed at the point of sale, added on top of the listed price. Unlike VAT systems in many other countries, US prices on shelves and menus typically do not include tax, which means the amount you pay at the register is higher than the sticker price. Rates vary widely—from 0% in states like Oregon and Montana to over 10% in some cities when state, county, and municipal taxes are combined.
This calculator is especially helpful when shopping across state lines, comparing online versus in-store prices, or budgeting for large purchases like electronics, furniture, or vehicles.
How to use it
- Enter the item price (pre-tax amount).
- Enter the sales tax rate as a percentage (e.g. 8.25%).
- Read the tax amount and total price in the results.
- To reverse-calculate: enter the total (tax-included) price and the rate to find the pre-tax amount.
Formulas used
Tax amount = Price × (Tax rate / 100) Example: $299.99 × 0.0825 = $24.75
Total price = Price + Tax amount Example: $299.99 + $24.75 = $324.74
Pre-tax price from total (reverse): Pre-tax = Total / (1 + Tax rate / 100) Example: $324.74 / 1.0825 = $299.99
Examples
Example 1 — Electronics purchase in Texas (8.25%): Price = $499.00. Tax = $499.00 × 0.0825 = $41.17. Total = $540.17.
Example 2 — Restaurant meal in New York City (8.875%): Subtotal = $86.50. Tax = $86.50 × 0.08875 = $7.68. Total = $94.18 (before tip).
Example 3 — Reverse calculation: You paid $53.50 total in a state with 7% tax. Pre-tax price = $53.50 / 1.07 = $50.00. Tax was $3.50.
Tips and common mistakes
- Look up your combined rate. Your total sales tax is often the sum of state + county + city rates. A "6% state tax" might actually be 8.5% or more once local surcharges are added. Check your local government website or receipt.
- Some items are exempt. Many states exempt groceries, prescription medication, and clothing (up to a threshold) from sales tax. Know your state's exemptions.
- Online purchases are taxed too. Since the 2018 Supreme Court ruling in South Dakota v. Wayfair, most online retailers collect sales tax based on the buyer's location.
- Tax holidays exist. Some states offer annual sales tax holidays (often in August for back-to-school shopping) where certain items are tax-free.
- Vehicle and property sales tax may use different rates or be calculated differently than general merchandise. Always check with your local DMV or tax assessor for big-ticket purchases.
- Round to the nearest cent. Tax calculations often produce fractions of a cent; standard practice is to round to two decimal places using normal rounding rules.