Sales Tax Definition The Sales Tax Calculator will calculate the sales tax for any item if you enter in the total purchase amount and the sales tax percentage. The Sales Tax Calculator will not only calculate sales tax but also show you the total amount that you will have to pay after including the sales tax. Our free online sales tax calculator makes calculating sales tax online easy! Check out the Reverse Sales Tax Calculator as well to calculate how much your item was without sales tax included.
How to Calculate Sales Tax Let's be honest - sometimes the best sales tax calculator is the one that is easy to use and doesn't require us to even know what the sales tax formula is in the first place! But if you want to know the exact formula for calculating sales tax then please check out the "Formula" box above.