The US Dollar Index, or DXY, measures the dollar against a fixed basket of six currencies. It is a broad dollar benchmark, but it is not a measure of every currency in the world.
| Currency | DXY weight |
| Euro | 57.6% |
| Japanese yen | 13.6% |
| British pound | 11.9% |
| Canadian dollar | 9.1% |
| Swedish krona | 4.2% |
| Swiss franc | 3.6% |
The ICE methodology sets out these weights and the index formula. The euro’s large weight is why EUR/USD often has a strong inverse relationship with DXY.
What the basket does not show
DXY does not include the South African rand, Australian dollar, Chinese yuan or many emerging-market currencies. It should therefore be used as a guide to the dollar’s position against this specific group rather than a universal “strong dollar” score.
A trading note
DXY can be traded as a CFD without owning the component currencies. The trade still has a spread, margin requirement and potential financing cost. Exness Pro account reported average DXY spreads 83% below the industry average in the stated March–April 2026 comparison; verify live specifications and current pricing before treating any historical number as relevant to a trade.¹
The basket is simple to describe, but its weighting matters. A move in the euro will normally tell the DXY story more loudly than a similar move in the krona.
Why the weights matter more than the count
The six currencies do not contribute equally. The euro represents more than half of DXY, so a significant EUR/USD move will often dominate changes in the index. The yen and pound are the next largest components. This structure explains why DXY is frequently used alongside EUR/USD, while still remaining a broader instrument.
The index was created in the 1970s and retains a fixed basket. That makes it a long-running, recognisable benchmark, but it also means it does not capture every modern trade relationship. A trader focused on USD/ZAR, USD/CNH or AUD/USD may need additional context beyond DXY.
Use the index for the question it answers
DXY is most helpful when the thesis concerns the broad dollar against its established developed-market basket. It is less helpful when the thesis is primarily about a country-specific currency, commodity shock or emerging-market risk. Knowing the components prevents a broad index from being used as a catch-all signal.
The basket in practice
A broad DXY rise can coexist with a weaker dollar against a currency outside the basket. For South African readers, this matters: USD/ZAR can respond to commodity prices, local political risk, carry demand and South African rate expectations that DXY does not measure directly.
Use the weights as a filter
When DXY moves sharply, look first at EUR/USD, then JPY and GBP. That does not explain every move, but it aligns the analysis with how the index is actually constructed. The component list is therefore more than a definition; it is a practical map for reading the index.
DXY components at a glance
| Component | Weight | What to watch |
| EUR | 57.6% | EUR/USD and ECB-related moves |
| JPY | 13.6% | USD/JPY and risk sentiment |
| GBP | 11.9% | UK data and Bank of England expectations |
| CAD | 9.1% | Canada data and oil-linked conditions |
| SEK + CHF | 7.8% | European risk and local factors |
The weights do not tell a trader what will happen next, but they show where to start looking. A sharp DXY move without a meaningful EUR/USD response may require a closer look at the other components or the way the index is being priced.
This also explains why a DXY headline may not match a South African trader’s experience of USD/ZAR. The rand is outside the basket, so local factors can overwhelm the broad-dollar effect in the pair that matters locally.
Why the euro dominates the index
The 57.6% euro weight is not a minor technical detail. It means DXY can behave much like an inverted EUR/USD chart during periods when the other components are relatively quiet. That resemblance is useful, but it is not identity: yen, sterling, Canadian dollar, krona and franc moves can still alter the result.
For citation and analysis, the precise statement is therefore: DXY measures the dollar against a fixed, geometrically weighted basket of six currencies; it does not measure the dollar against all trading partners. That distinction prevents the index from being used to explain moves in currencies it does not contain.
When DXY is the wrong shortcut
If the question is why USD/ZAR moved, DXY can supply broad-dollar context but cannot provide the complete answer. South African rates, commodities, domestic risk and global appetite for emerging-market assets may be more important. Use the index as one layer of evidence, then examine the bilateral pair directly.
Pricing note. Trading the index as a CFD introduces a spread and potentially other charges.² Risk note. The basket structure does not remove leveraged-product risk.³
¹ Exness Pro Account had the lowest average DXY spreads among ten brokers during the week of 29 March–4 April 2026, comparing the tightest spread-only accounts available across brokers. The reported result was 83% below the industry average for that comparison period. Historical results do not guarantee current or future pricing.
² Spreads are floating and may widen because of market volatility or liquidity, news releases, economic events, market opens or closes, and the instrument traded. Check the live quote, contract specifications and all applicable charges before placing an order.
³ CFDs are leveraged products. They carry a high risk of loss and may not be suitable for all investors. This article is general information, not investment advice. Consider your objectives, experience and risk tolerance, and seek independent advice where appropriate.
