The foreign exchange rate is the exchange rate at which one country's currency is converted into another country's currency, or the price of another country's currency expressed in one country's currency.

Exchange rate is also called exchange rate, and it is also called foreign exchange quotation in actual foreign exchange trading business. The exchange rate form of Party A and Party B's currencies is usually written as: Currency A/ Currency B, for example, the exchange rate of US dollar against Japanese yen can be written as USD/JPY. Among them, the one on the left of the diagonal is called the benchmark currency, and the one on the right of the diagonal is called the quotation currency.