The dollar index rose 0.1 percent to 95.934, hovering just below the 96.108 mark touched on Friday that was the highest since Sept. 1. The dollar has fallen against the six major currencies that make up its basket in three of the past four sessions, but had its largest one-day percentage gain since late July on Friday.
Esther Reichelt, a currency strategist at Commerzbank Frankfurt, said she expected a quiet day, though thin trading could lead to some exaggerated moves not driven by fundamental factors.
"Everybody is just waiting for the BOJ and the Fed. Why do anything today?" she said. "Everyone has already positioned for these events and there is no new information that could give them a reason to reposition, so I expect a rather calm day."
The dollar got its biggest boost on Tuesday from selling of the British pound, which dipped 0.5 percent to its lowest against the greenback since Aug. 16 on worries about the political and economic risks from Britain's pending exit from the European Union.
The head of Germany's Bundesbank warned on Monday that banks based in Britain could lose "passporting" access to EU markets after Brexit.