Coining money refers to the process of creating currency, typically in the form of coins, that is used as a medium of exchange. The power to coin money is granted to Congress in the United States Constitution, which gives Congress the power to "coin Money, regulate the Value thereof, and of foreign Coin, and fix the Standard of Weights and Measures". This means that Congress has the authority to create and regulate the currency of the United States, including the power to determine the value of the currency.

In addition to creating coins, Congress also has the power to issue paper money and other forms of currency. The establishment of a single national currency was considered an important function of government by the framers of the Constitution. Initially, only gold coins were issued, but the authority to issue bank notes was later granted to the First Bank of the United States in 1791.

The term "coin money" can also be used informally to refer to the act of making a great deal of money easily or very quickly.