What Is the US Dollar Index (DXY)?
You’ll often hear that “the dollar” rose or fell — but against what? The US Dollar Index, or DXY, is the single number that answers that question.
What it measures
The DXY tracks the dollar against a basket of six major currencies — chiefly the euro, plus the yen, pound, Canadian dollar, Swedish krona and Swiss franc. The euro dominates the basket, so DXY is heavily a euro-dollar story.
How to read it
When the index rises, the dollar is strengthening against those currencies on average; when it falls, it’s weakening. It’s a quick gauge of overall dollar strength rather than any single pair.
Why it matters beyond trading
A strong dollar (high DXY) makes commodities like oil and gold — priced in dollars — more expensive for the rest of the world, and can strain countries with dollar debts. So the DXY ripples far beyond currency markets.
The limitation
The basket is old and Europe-heavy — it ignores the Chinese yuan and many big economies. It’s a useful shorthand, not the whole picture. For any specific pair, use our live converter; for the forces behind dollar strength, see why the dollar is so strong.