This tool can be used to perform value-added tax (VAT), goods and services tax (GST), or sales tax calculations. It will help you quickly add tax value to the initial price, or subtract the tax value from the total price in order to calculate the initial value.
Enter a number in either field, then click outside of the text box.
See also:
Wikipedia - Value-added tax
Wikipedia - Sales tax
Unit Converters and Calculators - extended list