The dollar fell to a record low against the euro after the Federal Reserve cut its benchmark interest rate by a quarter-percentage point and said the pace of economic growth will slow this year.
The euro jumped to $1.4494, a record high and up 0.4 percent on the day, according to Reuters data.
The dollar fell against the yen, trading at about 114.95 yen against about 115.25 yen shortly prior.
The dollar had gained earlier after a stronger-than expected U.S. private-sector jobs report and advanced estimates showed the economy grew at its fastest pace in the third quarter since the beginning of last year.
But gains reversed on nervousness about the decision by the Fed's policy-making Federal Open Market Committee later in the day and a subpar reading of October business activity in the U.S. Midwest.
The Australian dollar rose to a 23-year high against the U.S. dollar after the cut encouraged investors to buy higher-yielding currencies.
The Australian dollar jumped to US$0.9328, the highest since 1984, according to Reuters data. The currency has gained 18 percent so far versus the greenback since the beginning of the year.