The U.S. dollar index is a comprehensive indicator that measures the exchange rate changes of the U.S. dollar in the international foreign exchange market. It is composed of the U.S. dollar against six major international currencies (euro, Japanese yen, British pound, Canadian dollar, Swedish krona and Swiss franc). The exchange rate is calculated as a weighted geometric mean.

The U.S. dollar exchange rate refers to the ratio of the U.S. dollar to another country’s currency unit. It can also be said to be the price of another country’s currency expressed in U.S. currency.