Focusing the Fed on the Currency of the United States Act of 2013, or FFOCUS Act of 2013 - Amends the Federal Reserve Act to repeal the joint mandate on the Board of Governors of the Federal Reserve System and the Federal Open Market Committee to make maximum employment one of the goals of their duty to maintain long run growth of the monetary and credit aggregates commensurate with the U.S. economy's long run potential to increase production.