DXY (US Dollar Index)
The DXY, or US Dollar Index, measures the value of the US dollar against a fixed basket of six major currencies. A rising DXY means the dollar is strengthening; crypto prices have often, but not always, moved the opposite way.
How the index is built
The index started at a value of 100 in March 1973, shortly after the end of fixed exchange rates, and is now published by Intercontinental Exchange (ICE). It is a weighted geometric average of the dollar's exchange rate against six currencies. The weights have only changed once, in 1999, when the euro replaced several European currencies in the basket.
The euro makes up about 57.6% of the index, followed by the Japanese yen at 13.6%, the British pound at 11.9%, the Canadian dollar at 9.1%, the Swedish krona at 4.2% and the Swiss franc at 3.6%. So the DXY is largely a euro-dollar measure and leaves out major trading partners such as China and Mexico.
Reading the number
A reading of 105 means the dollar is worth about 5% more against the basket than it was at the 1973 base. Say the index rises from 100 to 110 over a year: on average the dollar now buys roughly 10% more of those currencies, and everything priced in dollars, including bitcoin, looks more expensive to buyers paying in euros or yen.
Why it matters for crypto
The dollar tends to strengthen when US interest rates rise relative to other countries or when investors seek safety. Both conditions usually mean tighter financial conditions and less appetite for risky assets, a risk-off environment. When the dollar weakens, liquidity and risk appetite often improve. That is why a strong DXY has frequently coincided with weak crypto prices, as in 2022, when the index climbed above 110 while the Federal Reserve raised rates and crypto markets fell sharply.
Limits of the relationship
Correlation is not causation, and it is not stable. There have been long stretches where crypto and the dollar moved together or independently, driven by crypto-specific events such as exchange failures, ETF approvals or halvings. The DXY also reflects what happens to the euro and the yen, not only the dollar. Use it as context for the macro backdrop, not as a trading trigger.
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Frequently asked questions
Is DXY the same as the dollar index?
Yes. DXY is the ticker commonly used for the ICE US Dollar Index. The Federal Reserve also publishes a broader trade-weighted dollar index, which uses many more currencies.
Why does a strong dollar often hurt crypto?
A strong dollar usually reflects higher US rates or demand for safety, which tightens global liquidity and reduces appetite for risky assets like crypto.
Does the DXY include the Chinese yuan?
No. The basket has only six currencies, the euro, yen, pound, Canadian dollar, Swedish krona and Swiss franc.
Related terms
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