Category: Calculators
Sales Tax Calculator
Add a tax rate, or take it back out
Add a tax rate to a net price, or pull the tax back out of a price that already includes it. Enter the rate that applies where you are and read the net amount, the tax and the total.
The rate is the one you type. Nothing is looked up, so check the rate that applies where you are before relying on the result.
Everything on this page is processed in your browser. Nothing is uploaded.
What this tool does
Adding tax is the easy direction. The one people get wrong is the other: the tax inside a tax-inclusive price is not the price times the rate, it is the price minus the price divided by one plus the rate. On a 100 total at 20%, that is 16.67 of tax and 83.33 net, not 20 and 80. This tool does both directions from the same two fields, with presets for the rates that come up most often and room to type any other. It works the same whether your invoice calls it sales tax, VAT or GST, because the arithmetic does not change with the name.
How to use it
- Choose whether you are adding tax to a net amount or removing it from a total.
- Enter the amount and the tax rate that applies to you.
- Read the amount before tax, the tax itself and the total.
Privacy
This tool runs entirely in your browser. Your input is never uploaded, stored or shared — closing the tab removes it.
Frequently asked questions
- Are my amounts sent anywhere?
- No. The calculation happens in the page and nothing is uploaded or saved.
- Does the tool know my local tax rate?
- No, and deliberately so: rates differ by country, state, county and product, and change without notice. Looking one up would mean shipping a table that is wrong somewhere. Type the rate that applies to you.
- How do I find the tax inside a price that already includes it?
- Choose Remove tax. The tool divides by one plus the rate to recover the net amount, then reports the difference as the tax.