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Sales Tax Calculator

The price on the tag is rarely the price you pay. Use this calculator to find the total cost including state and local sales tax, so you're not surprised at the checkout.

Reviewed by David Chen, CFA | Last Updated: November 2025
Tax Amount: $8.50
Total Price: $108.50

Understanding Sales Tax

Sales tax is a consumption tax imposed by the government on the sale of goods and services. In the United States, it's complicated because it's not just a federal tax—it's a mix of state, county, and city taxes.

Expert Tip from David Chen, CFA

"Don't forget that tax rates change based on where you *receive* the item, not just where you buy it. If you're buying a car or ordering online, the tax rate is usually based on your delivery address, which could save (or cost) you money depending on your local laws."

How to Calculate Sales Tax Manually

The math is straightforward:

Tax Amount = Price × (Tax Rate / 100)
Total Price = Price + Tax Amount

Common Mistake: Forgetting Local Taxes

Many people only look up their state's sales tax (e.g., California is 7.25%). But most cities add their own district taxes, pushing the real rate much higher (e.g., Los Angeles is 9.5%). Always check the total combined rate for your specific zip code.

Reverse Sales Tax Calculation

Need to know the price before tax? Divide the total by 1 + (tax rate / 100).
For example, if you paid $108.50 with 8.5% tax:
$108.50 ÷ 1.085 = $100.00.