What Is the DXY?

The US Dollar Index, ticker DXY, measures the value of the US dollar against a fixed basket of six other currencies. It doesn't tell you the dollar's value in isolation — currencies only have meaning relative to something else — so DXY expresses the dollar's overall strength as one number that rises when the dollar strengthens against that basket, and falls when it weakens.

Six currencies make up the index, each with a fixed weight set when the index was created in 1973: the euro (EUR, ~57.6%), Japanese yen (JPY, ~13.6%), British pound (GBP, ~11.9%), Canadian dollar (CAD, ~9.1%), Swedish krona (SEK, ~4.2%) and Swiss franc (CHF, ~3.6%). The euro's outsized weight means EUR/USD is by far the biggest single driver of DXY's day-to-day moves — when the euro moves sharply, DXY usually moves with it, even if the other five currencies are quiet.

The basket and its weights are fixed and haven't been rebalanced since the euro replaced the original European currencies in 1999 (before that, DXY tracked the deutsche mark, French franc, and several others that the euro absorbed). That's a deliberate design choice for continuity — it makes DXY comparable across decades — but it also means the index doesn't reflect today's actual pattern of US trade, which now leans more heavily on partners like China and Mexico that aren't in the basket at all.

Because it's dominated by the euro, yen, pound and Canadian dollar, DXY tends to move on the same drivers as those pairs: Federal Reserve policy and US Treasury yields relative to other central banks, risk sentiment (the dollar often strengthens when markets get nervous), and economic data surprises — employment, inflation and growth prints — that shift expectations for where rates are headed. See Federal Reserve, Rates and the Dollar Index for how that specific link works, and DXY Forecast and Outlook for how to read the index's current setup.