Sales Tax Calculator
Calculate the sales tax amount and the total price including tax.
Enter amount and tax rate.
What This Calculator Does
This tool answers the question you're actually asking at checkout: given a price and a tax rate, what's the tax amount, and what's the total you'll actually pay? Enter the pre-tax amount and your local tax rate as a percentage, and it returns both figures — the tax itself and the final total — without you needing to do the multiplication by hand.
How to Use It
Enter the Original Amount and the Tax Rate as a percentage — for example, enter 8.25 for an 8.25% rate, not 0.0825. The result shows the Original Amount you entered, the Tax Rate applied, the tax amount itself, and the Total Amount with tax added, so there's no ambiguity about which figure is which when you're reading it back.
The Formula
Tax Amount = Original Amount × (Tax Rate ÷ 100), and Total Amount = Original Amount + Tax Amount. Both figures are rounded to the nearest cent using standard half-up rounding, matching how a cash register or point-of-sale system displays a tax line — so a computed tax of, say, $1.1994 is what you'd see rounded to $1.20 on the result.
A Worked Example
An $80.00 purchase at 8.25% — a real Texas state sales tax rate — comes to a tax amount of $80.00 × 0.0825 = $6.60 exactly. Add that to the original $80.00 and the Total Amount comes to $86.60. Since 8.25% of $80 happens to divide out evenly, this example has no rounding to worry about, but the same two-step formula applies regardless of whether the numbers land on a clean cent or not.
FAQ
- How is sales tax calculated?
- Multiply the original amount by the tax rate percentage and divide by 100. The calculator does this automatically — just enter your values.
- Can I calculate tax for different states?
- Yes, enter the applicable tax rate for your state or region. Common US rates range from 0% to 10%+.