Sales Tax Calculator

What this sales tax calculator does

You know the price. You know the rate. You want to know what actually leaves your account at the till, or what to put on the invoice.

Give this calculator the price before tax and the rate as a percentage, and it hands back the tax and the total. That is the whole job, and it is deliberately unopinionated about where you are. No state list, no country list, no assumptions about what is taxable. You bring the rate, it does the arithmetic.

Which makes it useful in places the jurisdiction specific tools are not. GST in Nepal or India, VAT anywhere, US state and local combined, a provincial rate in Canada, or a made up figure because you are testing something. It does not care.

If you are in the United States and want the rate broken into state and local parts, our US sales tax calculator splits them. For VAT specifically, including working backwards from a gross figure, the VAT calculator handles both directions.

Everything runs in your browser. Nothing typed here is stored or sent anywhere.

How to use it

1. Cost/Price. The price before tax. No currency symbol needed, and none is assumed.
2. Sales Tax. The rate as a percentage, so type 8.25 rather than 0.0825. Anything above 100 is refused, which is fair enough.

Press Calculate for the tax and the total. Press Reset to clear it.

One thing to be clear about, because it is the single most common way people get a wrong answer here. This tool goes forwards only, from a pre tax price to a total. If the number you have already includes tax and you are trying to work out how much of it is tax, feeding it in here will not do that. The section below shows you how to do it properly, and it takes about ten seconds.

The formula

Two lines, and the second one is just the first one plus the price.

Tax = price × (rate ÷ 100)

Total = price × (1 + rate ÷ 100)

That is genuinely all of it. Sales tax is one of the few things in finance where the arithmetic really is as simple as it looks, and where all the difficulty sits somewhere else entirely, namely in working out which rate applies to what you are buying and where.

A worked example: 19.99 at 8.25 percent

A shirt marked 19.99, in a place with a combined rate of 8.25 percent.

The tax is 19.99 × 0.0825 = 1.65.

The total is 19.99 + 1.65 = 21.64.

A shortcut worth carrying around. To get the total in one step, multiply by 1.0825 rather than working out the tax and adding it. 19.99 × 1.0825 = 21.64. Same answer, one operation, and it scales to any rate. Ten percent is × 1.1, twenty percent is × 1.2, and so on.

The reverse of that shortcut is what makes the next section work, so it is worth getting comfortable with.

Taking the tax back out of a total

This comes up constantly. You have a receipt showing 108.25 and you need to know how much of that was tax, because you are reclaiming it, or splitting a bill, or filling in a return.

Here is the mistake almost everybody makes first. They take the total and multiply it by the tax rate.

That is wrong, and it is wrong in a specific direction: it always gives you too much. On a gross figure of 120 at 20 percent, multiplying gives you 24. The real tax is 20. You have overstated by 4, and you have done it because you applied the rate to a number that already had the tax inside it.

The right way is to divide, not multiply:

Net price = gross ÷ (1 + rate ÷ 100)

Tax = gross − net

So on that 108.25 receipt at 8.25 percent: 108.25 ÷ 1.0825 = 100.00 net, and the tax was 8.25.

Check it forwards to be sure. 100 × 1.0825 = 108.25. It closes, so the split is right.

The reason the multiplication fails is worth understanding once rather than memorising. The rate is defined as a percentage of the net price, not of the total. Once tax is in the number, the base has changed, and applying the same percentage to a bigger base gives a bigger answer. Divide to undo it.

Why the shelf price is not what you pay

If you have ever shopped in the United States after living almost anywhere else, you will have had the small shock of the till asking for more than the label said. That is not a scam, it is a genuinely different convention, and it is why a calculator like this gets used so much in one country and so little in others.

Tax exclusive pricing, which is the American norm, displays the price before sales tax and adds it at checkout. There is a practical reason for it. The combined rate changes from one city to the next, sometimes across a street, so a national retailer cannot print one tax inclusive price on a label or in an advert.

Tax inclusive pricing, which is the norm across the UK, the EU, and most of Asia, shows consumers the final price with VAT or GST already in it. In the UK that is a legal requirement for consumer pricing, which is why the number on the tag is the number you hand over.

So the practical rule when you are travelling or buying across borders. In the United States, assume the price will grow by somewhere between nothing and about ten percent depending on where you are standing. Almost everywhere else, assume the price is the price. And if you are a business quoting to customers in another country, be explicit about which one you mean, because "500 plus tax" and "500 including tax" are two rather different offers.

Where the cents land

The results here are shown to three decimal places rather than two, which you will notice on awkward numbers. That 19.99 at 8.25 percent produces a tax of 1.649 rather than 1.65.

Both are the same figure, just displayed with more precision than money usually is. Round it to two decimals yourself and you have what a till would charge. We are tidying that display.

The wider point is worth a moment though, because rounding on sales tax is genuinely not standardised. Most retailers calculate the tax on the whole basket and round once at the end, which is the sensible approach and the one this calculator matches if you enter your basket total. Some systems calculate per line item and round each one, which can put you a cent or two out on a long receipt. And a handful of US states historically published bracket tables that specify the exact tax due at each price point rather than leaving it to arithmetic.

None of this matters on a shirt. It matters quite a lot if you are reconciling a month of transactions and cannot work out why you are eleven cents adrift.

Questions people ask

How do I work out the tax that is already included in a price?

Divide the total by 1 plus the rate as a decimal, then subtract. A total of 108.25 at 8.25 percent divides by 1.0825 to give a net of 100, so the tax was 8.25. Do not multiply the total by the rate, it overstates.

Which currency does it use?

None at all, on purpose. Put in rupees, dollars, pounds, naira. Percentages behave identically in every currency.

Can I use it for VAT or GST?

Yes, for adding tax to a net price the arithmetic is identical. For VAT work where you need to go both directions, the VAT calculator is built for it.

What if I have state and local tax separately?

Add them together and enter the combined figure. Sales taxes stack additively, they are not applied on top of each other. A 7.25 percent state rate and a 2.5 percent local rate is 9.75 percent, not 9.93.

How do I know what rate applies to me?

That is the genuinely hard part and no calculator can answer it, because it depends on where the sale happens and what is being sold. Your local tax authority is the answer. For the United States, our US sales tax calculator page points you at the right sources.

Do I apply tax before or after a discount?

After. Tax is charged on what you actually pay, so take the discount off first and then run the discounted price through here.

References

A note on sourcing. The arithmetic here is universal, but the rate that applies to any given sale is set by a specific tax authority. The sources below are the primary published references for the two largest systems this calculator gets used with.

1. HM Revenue and Customs, VAT Rates, GOV.UK. https://www.gov.uk/vat-rates
2. Tax Foundation, State and Local Sales Tax Rates, 2026. https://taxfoundation.org/data/all/state/sales-tax-rates/
3. HM Revenue and Customs, Rates of VAT on Different Goods and Services, GOV.UK. https://www.gov.uk/rates-of-vat-on-different-goods-and-services