In the united states today, what gives money its value?

The value of any money is determined by supplys and demands and the supplys and demands for other goods in the economy

The value of any good is determined by its supply and demand and the supply and demand for other goods in the economy. A price for any good is the amount of money it takes to get that good. Inflation occurs when the price of goods increases-in other words when money becomes less valuable relative to those other goods.