What Is the US Dollar Index (DXY) and How to Read It
Sep 19, 2026 · 4 min read
DXY is the most quoted gauge of the dollar, but it covers only six currencies and leans heavily on the euro. Here is what it shows and what it leaves out.
What DXY is
The US Dollar Index measures the dollar against a fixed basket of six currencies: the euro, Japanese yen, British pound, Canadian dollar, Swedish krona and Swiss franc. It began in 1973, and its composition has barely changed since the euro replaced several European currencies.
The weights matter
The euro makes up well over half of the index. A move in the euro against the dollar therefore explains most of the move in DXY. When the index rises, the dollar is stronger against that basket; when it falls, it is weaker.
How to read a move
A rising DXY often coincides with higher US yields, stronger US data, or a flight to safety. A falling DXY often follows expectations of lower US rates or improving global growth. Because many commodities, including gold and oil, are priced in dollars, a stronger dollar tends to weigh on them, though other forces can override that link.
What DXY leaves out
It excludes the Chinese yuan, the Mexican peso and other currencies that matter for US trade. Broader trade-weighted indices exist for that reason. DXY is best used as a quick summary of dollar direction against developed-market currencies, not as a full picture.
Practical tip
When a headline says the dollar rose, check which currencies drove it. A move led by the yen tells a different story from one led by the euro.
