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Estimate the final checkout total when you know the local sales tax rate.
Last updated: October 2026
Estimate checkout total from price and tax rate.
Sales tax in the United States depends on state, county, and city rules. This calculator helps estimate a final price when you already know the tax rate.
Sales tax = price × tax rate. Final total = price + sales tax.
Use your local rate from a receipt, store checkout page, or official local source for the best estimate.
It estimates the sales tax amount and final checkout total when you already know the tax rate that applies, which is useful for budgeting a purchase, checking a receipt, or comparing prices across areas with different tax rates.
A $99.99 item at an 8.25% sales tax rate comes to about $8.25 in sales tax, for a final total of roughly $108.24. Comparing that same item at a 6% rate versus a 9.5% rate shows a difference of a few dollars — small on a single item, but worth checking on larger purchases.
Check a recent store receipt, the store's checkout page, or your state or county government's official revenue website for the most accurate current rate.
In the US, sales tax is set at the state level and often layered with additional county and city rates, so the combined rate can differ significantly even between nearby locations.
You can use it as a general estimate, but online retailers typically calculate tax based on your shipping address and their own registered tax jurisdictions, which may differ from a simple flat-rate estimate.
No. Many jurisdictions exempt or reduce tax on categories like groceries, prescription medication, or clothing. Check your local rules if you're estimating tax for one of these categories.
In depth
U.S. sales tax is set by states, counties, cities and special districts, so the rate at checkout depends on exactly where you are and sometimes on what you are buying. This section covers the three calculations people need most and the rules that cause surprises.
Tax = price × rate; total = price × (1 + rate). A $59.99 item at an 8.25% combined rate has $4.95 of tax (rounded to the cent), for a total of $64.94.
To recover the pre-tax price, divide by (1 + rate), not multiply by (1 − rate). A $107.25 receipt at 7.25% came from a $100.00 price: 107.25 ÷ 1.0725 = 100. Subtracting 7.25% of $107.25 instead gives $99.47, which is wrong by 53 cents. The gap grows as the amount and the rate grow.
Rate = tax charged ÷ pre-tax subtotal. If a $40.00 subtotal shows $3.30 of tax, the combined rate is 8.25%. That is useful for checking whether a receipt used the right local rate.
In the U.S., shelf prices usually exclude tax. In the UK and most of Europe, consumer prices include VAT. If you are converting a European price for comparison, remove the VAT first. The sales tax vs. VAT guide explains the difference.
Retailers round tax to the nearest cent, and they may calculate it per line item or on the whole order. A one-cent difference between the calculator and a receipt is normal.