Online Tool Store
Sales Tax Calculator
Calculate sales tax and final price, or reverse an after-tax total to find its pre-tax amount, with clear results directly in your browser.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Example shown: $125.00 with an 8.25% sales tax rate.
Pre-tax price
$125.00
Sales tax
$10.31
Total price
$135.31
How sales tax is calculated
- Enter a pre-tax price or switch to an after-tax total.
- Enter the combined sales tax rate for the transaction.
- Review the base price, tax amount, and final total.
The formulas
To add tax, multiply the base price by the rate divided by 100. To reverse tax, divide the final total by one plus that decimal rate.
tax = price x rate / 100
pre-tax price = total / (1 + rate / 100)
FAQ
How do I calculate sales tax?
Multiply the pre-tax price by the tax rate as a decimal. Add that tax amount to the original price to find the final total.
How do I find a price before sales tax?
Divide the after-tax total by one plus the tax rate as a decimal. The difference between the total and that result is the included tax.
Does this tool look up local tax rates?
No. Enter the combined rate that applies to your transaction. Actual rates can vary by jurisdiction, product, and exemption.
Why can my receipt differ by a cent?
Stores may round tax per item or on the complete transaction. Different rounding sequences can produce a small difference.
Can I use currencies other than US dollars?
Yes. Choose USD, GBP, EUR, CAD, or AUD for formatting. The mathematics is identical and no exchange-rate conversion is performed.
How we compare
| Feature | Online Tool Store | Calculator.net | Avalara AvaTax |
|---|---|---|---|
| Add and reverse tax | Both modes | General sales-tax calculator | Automated tax determination |
| Rate source | User-entered rate | User-entered values | Jurisdiction and product rules |
| Best suited for | Quick single calculation | General calculations | Business tax automation |
Choose Calculator.net for a broad collection of related calculators or Avalara for business-grade jurisdiction and product tax automation. Choose Online Tool Store Sales Tax Calculator for a quick, private add-tax or reverse-tax calculation with no setup.