In his first Congress testimony on Tuesday, Powell said that despite recent volatility of the financial market, Fed governors still plan on hiking rates multiple times throughout 2018.
He pledged to "strike a balance" between the risk of an overheating economy and the need to keep growth on track.
Analysts said Powell's hawkish comments bolstered market speculations for as many as three rate-hikes later this year.
The dollar index, which measures the greenback against six major peers, was up 0.52 percent at 90.329 in late trading.
In late New York trading, the euro was down to 1.2236 dollars from 1.2310 dollars in the previous session, and the British pound decreased to 1.3917 dollars from 1.3966 U.S. dollars in the previous session. The Australian dollar was down to 0.7797 dollar from 0.7850 dollar.
The U.S. dollar bought 107.39 Japanese yen, higher than 106.93 Japanese yen of the previous session. The U.S. dollar increased to 0.9389 Swiss franc from 0.9380 Swiss franc, and it increased to 1.2752 Canadian dollars from 1.2680 Canadian dollars.
