US stocks have opened higher after mixed earnings and ahead of the start of a two-day meeting of Federal Reserve policymakers.

Five minutes into trade on Tuesday, the Dow Jones Industrial Average rose 75.07 (0.46 per cent) to 16,523.81.

The broad-based S&P 500 advanced 7.44 (0.40 per cent) to 1,876.87, while the tech-rich Nasdaq Composite Index gained 16.16 (0.40 per cent) to 4,090.56.

Corporate earnings season continued with pharmaceutical giant Merck besting expectations but tyremaker Goodyear falling short, in part due to a currency devaluation in Venezuela.

Investors were also keeping an eye on the Fed’s Federal Open Market Committee, which is expected to continue to scale back its bond-buying program but otherwise change nothing of substance in its policy statement.

“The consensus opinion is that there won’t be much, if any, change to the directive and that the FOMC will curtail its monthly asset purchases by another $US10 billion ($A10.8 billion) to $45 billion,” said Briefing.com analyst Patrick O’Hare.