The dollar gave back most of its gains from the past two days on Thursday as concerns about a smaller bond-buying program by the Federal Reserve dissipated.
A handful of strong earnings reports from overseas also drew investors to European stocks at the expense of investments seen as safer, such as the U.S. dollar.
The euro climbed to $1.3926 in late trading, versus $1.3761 late Wednesday.
The dollar's movements have largely been dictated in recent weeks by expectations that the Federal Reserve would announce a new bond-buying program aimed at stimulating the economy. The measures would lower U.S. interest rates and likely weaken the dollar against other currencies.
Reports in recent days that indicated the program might be smaller than anticipated gave the dollar some new life, but those gains appear to be fleeting.
The dollar dropped to 81.07 Japanese yen from 81.71 yen a day ago, pushing it back toward its 15-year low.
The British pound rose to $1.5931 from $1.5758 Wednesday.
The dollar also fell to 1.0212 Canadian dollars from 1.0298 Canadian dollars, and fell to 0.9832 Swiss francs from 0.9917 Swiss francs.