What Is the Dollar Index (DXY)?
The U.S. Dollar Index (DXY) measures the dollar's value against a fixed basket of six major currencies, so a rising DXY means the dollar is strengthening and a falling DXY means it is weakening. It is heavily weighted toward the euro, which alone makes up about 57.6% of the basket, so DXY is really a dollar-versus-Europe gauge as much as a broad one.
What DXY actually measures
The Dollar Index is a single number that tracks the U.S. dollar against six other currencies at once. It was created in 1973 with a starting value of 100.00, so a reading of 105 means the dollar is roughly 5% stronger than that 1973 baseline against the basket. When you hear a trader say "the dollar is up," they usually mean DXY is rising.
The index is a geometric weighted average, not a simple sum. The one thing most beginners miss: the weights are fixed and have not changed since the euro replaced several European currencies in 1999. That is why DXY does not include the Chinese yuan, the Mexican peso, or many currencies the U.S. trades heavily with today. It is a legacy basket, not a live trade-weighted measure.
The basket and its weights
DXY holds six currencies with these approximate fixed weights:
| Currency | Weight |
|---|---|
| Euro (EUR) | ~57.6% |
| Japanese yen (JPY) | ~13.6% |
| British pound (GBP) | ~11.9% |
| Canadian dollar (CAD) | ~9.1% |
| Swedish krona (SEK) | ~4.2% |
| Swiss franc (CHF) | ~3.6% |
Because the euro is more than half the basket, EUR/USD is by far the biggest driver. If the euro drops 1% against the dollar, DXY moves far more than an equal move in the krona would cause. Practically, DXY and EUR/USD trade almost as mirror images of each other. If you only watch one pair to explain a DXY move, watch EUR/USD.
What a rising or falling DXY signals
DXY is watched as a broad risk and macro barometer. A few common relationships traders track:
- Inverse to gold and commodities: Gold, oil, and many commodities are priced in dollars, so a stronger dollar often coincides with lower dollar prices for them, and a weaker dollar with higher prices. The link is a tendency, not a law.
- Inverse to non-USD forex pairs: A rising DXY tends to pressure EUR/USD, GBP/USD, and AUD/USD lower because the dollar is the quote currency in those pairs.
- Mixed with U.S. stocks: A sharply rising dollar can pressure large-cap multinationals that earn revenue abroad, since foreign earnings translate into fewer dollars. But in risk-off panics both the dollar and safe assets can rise together as investors seek safety.
- Rates and policy: DXY often climbs when U.S. interest rates rise relative to other countries, and softens when the Federal Reserve is expected to cut. This is why traders watch DXY closely around FOMC, CPI, and jobs data.
How traders use DXY day to day
Most active traders treat DXY as context, not as a standalone trade. If you are long a stock that sells heavily overseas, a fast dollar rally is a headwind worth noting. If you trade forex, DXY direction tells you whether the dollar is broadly bid or offered, which helps you avoid fighting the whole basket on a single pair.
A concrete example: say CPI comes in hotter than expected. Rate-cut odds fall, DXY spikes, EUR/USD sells off, and gold dips, all in the same minute. None of that is a signal to trade by itself; it is the macro weather that frames whatever setup you were already watching. If you want to see how DXY-style macro context gets folded into structured, trigger-based ideas, our signal cards spell out the trigger, targets, stop, and time-stop for every idea and keep the losers on the public record.
Where DXY comes from
The most-quoted index is ICE's U.S. Dollar Index (ticker DXY on ICE), and a nearly identical dollar index trades as futures. You will also see broader trade-weighted dollar measures published by the Federal Reserve that include more currencies like the yuan and peso. When people say "the dollar index," they almost always mean the six-currency ICE DXY, so know which one your data source is showing before you compare readings.
Want a room that reasons about the dollar, rates, and setups out loud? Join the free ClaudeQuantAlgo Discord for the public scoreboard, daily watchlist, and Academy fundamentals, no card required.
Common questions
Why is the euro such a large part of the DXY?
Does a strong dollar always mean stocks fall?
What is the difference between DXY and a trade-weighted dollar index?
Is the DXY inverse to gold?
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Last updated 2026-07-15 · ClaudeQuantAlgo Research Desk · research and education only.
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