The dollar's appreciation has "peaked" and the U.S. economy is "doing nothing," an economist has told CNBC.
The dollar fell against a basket of currencies on Friday, ending a decent month on a sour note.
The dollar rose to its highest level this week on Thursday after the U.S. Federal Reserve took another step towards raising interest rates.
The euro whipsawed against the dollar on Wednesday after the Federal Reserves said it would leave interest rates unchanged.
Emerging market currencies were eyed by investors on Wednesday as weak oil prices, China's market pain and after the Federal Reserve left its interest rates unchanged.
The U.S. dollar rebounded against the euro and yen on Tuesday after traders took profits from gains in those currencies.
The U.S. dollar hovered around a nearly two-week low against a basket of major currencies on Monday.
Robert Rennie, global head of FX strategy at Westpac Bank, expects factors such as the persisting slide in commodity prices and questionable growth in China to accelerate the fall in commodity currencies.
The dollar rose against a basket of currencies on Friday in choppy trade.
Paul Mackel, head of Asia currency research at HSBC, says the preliminary gauge of China's manufacturing activity signals that commodity currencies may face further downward pressure.
The euro strengthened on Thursday, briefly rising above $1.10 for the first time in a week.
The dollar rose after its biggest fall in a month the previous session, while sterling gained in response to minutes from the Bank of England's last meeting.
The dollar retreated from a three-month high against a basket of currencies on Tuesday on profit-taking.
Japan's benchmark stock index is in touching distance of an 18-year high, thanks to a weakened yen which has come back into focus as events in China and Greece die down.
Apart from supply issues, the drop in commodity prices also paints a weak picture for demand in Asia, says Sean Callow, senior currency strategist at Westpac.
The dollar reached its highest in three months against a basket of currencies on Monday.
The dollar was on track for its biggest weekly gain in two months on Friday as investors bet on the chances of a U.S. interest rate hike.
The dollar index rallied to a seven-week peak, with an easing in jobless claims reinforcing market expectations of a US interest rate hike.
The dollar rose on Wednesday after Federal Chair Yellen reinforced market expectations for a U.S. interest rate hike, possibly as soon as September.
The dollar posted moderate losses against the euro and yen on Tuesday.