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Sales Tax Calculator

Add sales tax to a net amount, or remove it from a tax-inclusive total. Enter the amount and rate and the tax and total update as you type.

Mode

Plain numbers, any currency. Calculated in your browser; nothing is uploaded.

Tax rate

Pick a common rate or type your own, decimals included. Leave blank or 0 for no tax.

Result

Enter the net amount to see the tax and total.

How to calculate sales tax online

  1. Choose add or remove tax

    Pick add tax to put tax on top of a net amount, or remove tax to back it out of a total that already includes it.

  2. Enter the amount and rate

    Type the amount and either tap a common rate or enter your own percentage. The figures appear as soon as the amount is valid, with no button to press.

  3. Read or copy the result

    The tax, the net amount, and the total update live. Copy the plain-text summary when you have the numbers you need.

Why use this tool

Add or remove tax in one place

Switch between putting tax on top of a net price and stripping it out of a tax-inclusive total without leaving the page.

Reverse a tax-inclusive total

Remove mode divides a gross total back into the amount before tax and the tax portion, so the two always add back to the total you entered.

Common rates or your own

One tap sets 5, 7, 8.25, 10, or 20 percent, and a custom field takes any other rate, decimals included. A blank or zero rate means no tax.

Exact two-decimal figures

Every amount is rounded to two decimal places and the tax and net always reconcile to the total, with no lost or extra cent.

Runs entirely in your browser

Everything happens on your device as you type. Nothing is uploaded, so the amounts you enter never leave the page.

About this tool

This sales tax calculator works in both directions. In add mode you type a net amount and a rate, and it shows the tax and the total with tax included. In remove mode you type a total that already has tax in it, and it backs the tax out to reveal the amount before tax and how much of the total was tax. Everything updates the moment the amount is valid, so there is no button to press.

Rates are never locked to a preset. Tap one of the common percentages or type your own, including decimals such as 8.25 or 7.5, and set it to zero when you just want to check a figure. All the money maths runs to two decimal places, and the tax and net always add back to the total exactly, so you never see a stray cent from rounding. The numbers are plain, with no currency symbol, so the result reads the same in dollars, euros, pounds, or any other currency.

Use add mode to see the shelf price plus tax before you buy, and remove mode to split a receipt total into the pre-tax price and the tax for an expense claim or a quick reconciliation. Everything is calculated on the page, so nothing you type is uploaded or stored. For working out a percentage of any number, the percentage calculator covers increases, decreases, and shares of a whole, and for taking money off a price rather than adding it on, use the discount calculator.

Frequently asked questions

What is the difference between add and remove tax?
Add tax starts from a net amount and puts the tax on top to give the total. Remove tax starts from a total that already includes tax and works backwards to the amount before tax and the tax portion.
How does removing tax from a total work?
The tax-inclusive total is divided by one plus the rate. For example, a 110.00 total at 10 percent gives 100.00 before tax and 10.00 of tax. The two figures always add back to the total you entered.
Can I use a rate of zero?
Yes. Leave the rate blank or set it to 0 and the tax is zero, so the total equals the net amount and remove mode returns the total unchanged. Any positive rate, with decimals, works too.
Which currency does it use?
None in particular. The calculator works with plain numbers to two decimal places, so the result reads the same whether you are working in dollars, euros, pounds, or any other currency.
Is my data uploaded anywhere?
No. Everything runs in your browser; nothing is sent to a server. The amounts and rate you type are never uploaded, stored, or logged.

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