Add up the amount of money that is to be changed. Every currency has an exchange rate relative to whatever currency is being exchanged.
Use a computer to go online and look for up-to-date exchange rates. These can be found on public banking websites, currency converters and financial websites. Search for the exchange rate between the two currencies you'll be changing.
Calculate the exchange rate by multiplying the total value of the currency possessed by the exchange rate for the target currency. For example, if Mr. Smith has $1000, and the exchange rate for Euros is 0.69, then multiply 1000 x 0.69 to get the equivalent total, which is €690.