Online Calculator

Sales Tax Calculator

United States sales tax rules vary not just by state but by county and city. This calculator works in both directions: compute the tax to add to a sticker price, or back out the tax already embedded in a receipt so you know the pre-tax cost.

Choose your state to preload typical combined rates, or type any custom rate for your exact locality.

Total with tax

$107.25

Before tax
$100.00
Sales tax (7.25%)
$7.25
After tax
$107.25

How the Sales Tax Calculator works

The calculation follows the standard method used across the US — no shortcuts, no hidden assumptions. Here is exactly what happens behind the scenes:

Formula

tax = price × rate ÷ 100;   gross = net × (1 + rate ÷ 100)
  • Adding tax: multiply the pre-tax price by the rate, add it to the price.
  • Removing tax: divide the gross price by 1 + rate/100.
  • The difference is the sales tax collected.

Frequently Asked Questions

Which US states have no sales tax?

Delaware, Montana, New Hampshire, and Oregon levy no statewide sales tax (Alaska allows local taxes only). Selecting those states sets the rate to zero.

Why does my city charge more than the state rate?

Most states allow counties and cities to stack local sales taxes on top. That is why the calculator lets you override the preset — check your exact combined rate on your state revenue department website.

How do I find the pre-tax price on a receipt?

Switch to “Remove tax”, enter the total you paid and the applicable rate. The tool divides the gross amount by (1 + rate), giving the net price and the exact tax portion.