Simple in use extension which allows to convert values of one currency to another. In addition it displays, in quick preview field, six user defined currencies. It has a lot of options that you can adjust to your needs.
By selecting any number on the page it will be copied to the extension. If you also select a text that represents a currency (name, symbol or currency code) it will select the proper value on the list as well.
Extension supports a lot of worldwide used currencies.
Since version 1.3.0, the add-on also allows you to perform simple mathematical operations in the field of the entered value, i.e. add, subtract, multiply and divide. The result of the operation is converted into individual currencies on an ongoing basis. The '=' button or enter button replaces individual operations with their result.