Highlights
- Foreign exchange is the largest and most liquid market in the world, trading continuously from Monday in Asia to Friday in New York.
- Currencies trade in pairs, so every quote expresses a relationship rather than an absolute value.
- Interest rate differentials are the dominant long run driver, because capital flows toward higher yields.
- Currency movement affects every investor with international exposure, including those who never trade forex directly.
- Retail forex trading is dominated by leverage, and leverage is where most retail losses originate.
What the Foreign Exchange Market Is
Foreign exchange is the market in which currencies are bought and sold. It has no central exchange. Trading occurs through a decentralised network of banks, brokers, institutions and electronic venues.
Turnover exceeds that of every other financial market by a wide margin, and the market operates around the clock on weekdays as trading passes between Asian, European and American centres.
Our forex market coverage follows the major pairs and the macroeconomic forces that move them.
How Currency Quotes Work
Every quote involves two currencies. In the pair EUR/USD, the euro is the base currency and the dollar is the quote currency. The price shows how many dollars one euro buys.
When the pair rises, the euro strengthened against the dollar, or the dollar weakened against the euro. Both statements describe the same event. This relational quality confuses newcomers, because a currency has no absolute value, only a value relative to something else.
A currency can therefore weaken against one counterpart while strengthening against another on the same day, which is why broad dollar indices exist to measure a currency against a basket rather than a single rival.
The Major Pairs
The most heavily traded pairs involve the United States dollar on one side, since it remains the dominant reserve and trade settlement currency.
EUR/USD carries the largest volume of any pair. USD/JPY is closely tied to the interest rate gap between the United States and Japan. GBP/USD reflects both British economic conditions and general risk appetite. USD/CHF is influenced by the Swiss franc’s status as a safe haven.
Pairs not involving the dollar, such as EUR/GBP or EUR/JPY, are known as crosses and typically carry lower volume and wider spreads.
What Drives Exchange Rates
Interest Rate Differentials
The dominant long run driver. Capital tends to flow toward currencies offering higher returns, all else equal. When a central bank raises rates or signals it intends to, its currency generally strengthens.
What matters is the expected path rather than the current level, because markets price anticipation. A rate rise that was fully expected may produce no reaction, while a change in tone about future policy can move a currency sharply.
Relative Economic Performance
Growth, employment and productivity affect the attractiveness of a currency over time. Persistent underperformance relative to trading partners tends to weaken a currency, particularly when it coincides with deteriorating public finances.
Trade and Current Account Balances
Countries importing far more than they export must acquire foreign currency to pay for it, which exerts downward pressure on their own. Persistent surpluses work in the opposite direction.
Risk Appetite
During periods of stress, capital moves toward currencies perceived as safe. Historically this has favoured the dollar, the Swiss franc and at times the yen. These flows can override interest rate logic entirely for a period.
Intervention
Central banks and finance ministries occasionally intervene directly, buying or selling their own currency to influence its level. Intervention produces sharp moves and is usually preceded by verbal warnings, which themselves move markets.
Why Currency Matters Even If You Never Trade It
An investor holding international assets is holding a currency position whether or not they intended to.
A foreign index rising ten percent while its currency falls ten percent against yours produces approximately no return. This effect is large enough to reverse apparent outperformance and is routinely omitted from cross border performance comparisons.
Currency also affects companies directly. Exporters benefit from a weaker home currency, since foreign earnings convert into more of it. Importers suffer. Indices heavy in international earners, such as the FTSE 100, frequently rise when the home currency falls, which looks counterintuitive until the mechanism is understood.
For households, currency determines the cost of imported energy, food and goods, and therefore feeds into inflation.
The Problem With Retail Forex Trading
Foreign exchange is widely marketed to retail participants, and the marketing emphasises accessibility while understating the central risk.
Retail forex is typically offered with high leverage, sometimes allowing positions many times larger than the deposit. Because major currency pairs move by small percentages on most days, leverage is what makes the activity appear worthwhile. It is also what makes losses arrive quickly.
A position leveraged thirty times requires only a small adverse move to eliminate the capital behind it. Regulators in several jurisdictions have capped retail leverage precisely because of documented loss rates, and many brokers are required to publish the percentage of retail accounts that lose money. Those figures are worth reading before opening an account.
Understanding currency markets is valuable for almost every investor. Trading them with leverage is a substantially different activity with a substantially different risk profile.
How to Follow Currencies Usefully
Track a broad dollar index rather than a single pair, since it measures the currency against a basket and filters out noise specific to one counterpart.
Watch interest rate expectations in the major economies, particularly changes in the expected path rather than announced decisions.
Note the currency exposure inside your own holdings. If a substantial portion of your portfolio sits in foreign assets, you already hold a currency view whether you chose one or not.
Pay attention to currency during earnings season, since multinational companies frequently attribute results in part to exchange rate effects.
Summary Keys
- Forex is the largest and most liquid market, trading continuously on weekdays without a central exchange.
- Currencies trade in pairs, so every quote is relational rather than absolute.
- Interest rate differentials are the dominant driver, with expectations mattering more than current levels.
- Risk appetite can override rate logic, driving capital toward currencies perceived as safe.
- International investors hold currency exposure whether or not they intended to, and it can reverse returns.
- Retail forex trading is defined by leverage, which is the principal source of retail losses.
Frequently Asked Questions
Why does a weaker currency sometimes lift a country’s stock market?
Because many large listed companies earn a substantial share of revenue abroad. When the home currency weakens, those foreign earnings convert into more of it, raising reported profits in local terms. Indices heavy in international earners, such as the FTSE 100 and the Nikkei 225, frequently rise when their currencies fall for exactly this reason. It reflects translation effects rather than improved underlying business conditions.
Do I need to hedge currency exposure in an international portfolio?
It depends on your time horizon and objectives. Over long periods currency effects have historically tended to partially offset, though not reliably. Over shorter periods they can dominate returns entirely. Hedged and unhedged versions of many international funds exist, with hedging adding cost. There is no universally correct answer, and it is a question worth discussing with a qualified regulated adviser who knows your situation.
Is forex trading suitable for beginners?
Understanding currency markets is valuable for everyone. Trading them is a different matter. Retail forex is typically offered with high leverage, and regulators in several jurisdictions require brokers to disclose the proportion of retail accounts that lose money, which is consistently high. Anyone considering it should read those disclosures, understand exactly how liquidation works, and treat the activity as high risk rather than as an accessible entry point to investing.
Where to Go Next
This guide expands the currency section of our complete markets framework, which covers every asset class, the global trading day and what drives prices across all of them.

