Forex API-Convert Historical Value from xignite converts an amount from one currency to another using the rate as of a specified historical date. Fixing time can be provided for rates that go back to 1/4/2010. Historical rates prior to 1/4/2010 are London midnight rates.
The API uptime is at least 99.9% and the data is updated in true real-time as new quotes are issued from market participants. Data is returned in XML, JSON, or CSV formats.