How to use the Sales Tax Calculator
- Enter the amount.
- Enter the sales tax rate for your area. Check your state, province or local authority for the current rate.
- Choose whether the amount is before tax (add tax) or already includes tax (remove tax).
- Read the total, the price before tax and the tax amount.
Formula used
Add tax: total = price × (1 + rate). Remove tax: price before tax = total ÷ (1 + rate), and tax = total − price before tax.
Worked example
Here is the Sales Tax Calculator worked through with the example values shown above, so you can check each step by hand.
| Inputs | |
|---|---|
| Amount | $100 |
| Sales tax rate | 8 % |
| Calculation | Add tax (amount is before tax) |
| Result | |
| Total including tax | $108.00 |
| Price before tax | $100.00 |
| Sales tax | $8.00 |
Tax on the default amount at different rates
For a price of 100 before tax.
| Sales tax rate | Sales tax | Total including tax |
|---|---|---|
| 5 % | $5.00 | $105.00 |
| 6 % | $6.00 | $106.00 |
| 7 % | $7.00 | $107.00 |
| 8 % | $8.00 | $108.00 |
| 10 % | $10.00 | $110.00 |
Adding sales tax to a price
Multiply the price by 1 plus the rate. An item priced at $100 with 8% tax costs $100 × 1.08 = $108.00, of which $8.00 is tax. A $249.99 item at the same rate costs $269.99.
The tax grows with the rate and the price. On a $1,000 purchase, tax is $50.00 at 5%, $70.00 at 7% and $100.00 at 10%.
Removing tax from a total
To find the price before tax from a total that includes it, divide by 1 plus the rate; do not subtract the percentage. For a total of $108 at 8%, the price before tax is $108 ÷ 1.08 = $100.00, and the tax is $8.00.
A common mistake is to take 8% off $108, which gives $99.36 and is wrong, because the 8% was charged on the smaller pre-tax price, not on the total.
Finding the right rate
Sales tax rates differ by country, state, county and city, and some items such as groceries, clothing or medicine may be taxed at a lower rate or not at all. Rates also change. Use the rate shown on your receipt or the official website of your tax authority, and treat the rates in any example here as illustrations only.
In some countries the equivalent tax is called VAT or GST and is usually included in the displayed price. The VAT calculator on this site works the same way with a rate field.
Practical uses
Use the calculator to budget for a purchase, to check a receipt, to separate tax on a business expense, or to work out the pre-tax price of an item advertised with tax included. Business owners can use it to check the tax portion of sales for bookkeeping.
For a purchase with several items taxed at different rates, calculate each item separately and add the results.
Frequently asked questions
How do I calculate sales tax?
Multiply the price by the tax rate as a decimal. At 8%, the tax on 100 is 8, and the total is 108.
How do I find the price before tax?
Divide the total by 1 plus the rate. At 8%, divide by 1.08.
Why not just subtract the percentage?
Because the tax was calculated on the pre-tax price, not on the total. Subtracting 8% from the total takes off slightly too much.
What is my local sales tax rate?
It depends on where you are. Check the official website of your tax authority or a recent receipt. Rates change, so confirm before you rely on one.
Is sales tax the same as VAT?
They are similar consumption taxes, but VAT is collected at each stage of production and usually shown in the price, while sales tax is added at the final sale.
Can I use this for GST?
Yes. The arithmetic is the same. Enter the GST rate and choose add or remove.
This calculator gives estimates for information only. Actual figures from a bank, employer, tax authority or doctor may differ. It is not financial, tax, legal or medical advice.