To find exchange rates, visit XE.com, X-Rates.com or Oanda.com. The sites offer current exchange rates and online currency converters for free. Banks, such as U.S. Bank and Bank of America, also provide exchange rates on their websites.
XE.com and X-Rates.com have the XE Data API that offers live rates for every currency in the world. XE.com also has the XE Rate Blender that monitors the quality of incoming data from over 160 sources worldwide to ensure accuracy. Oanda.com provides historical rates that date back to 1990, and an interactive graph that shows the daily average of the bid and ask rate prices.