What Is an Exchange Rate?

An exchange rate is simply the price of one currency expressed in terms of another. When you see EUR/USD = 1.08, it means one euro buys 1.08 US dollars. Every time you travel abroad, send money overseas, or buy goods from a foreign retailer, an exchange rate is working behind the scenes.

Understanding how these rates are set — and what causes them to move — can help you make smarter decisions whether you're an expat, a frequent traveler, or someone sending money home.

Currency Pairs Explained

Currencies are always quoted in pairs. The first currency in the pair is the base currency, and the second is the quote currency. The rate tells you how much of the quote currency you need to buy one unit of the base currency.

  • Major pairs — involve the US dollar and heavily traded currencies like EUR, GBP, JPY, CHF, AUD, CAD, and NZD.
  • Minor pairs — pairs between major currencies that don't include the USD (e.g., EUR/GBP).
  • Exotic pairs — one major currency paired with a currency from an emerging market (e.g., USD/THB).

Major pairs typically have tighter spreads (the difference between buy and sell prices) and more liquidity, making them cheaper to exchange.

What Moves Exchange Rates?

Exchange rates fluctuate constantly during market hours. Several key forces drive these movements:

  1. Interest rates — Central banks set interest rates. Higher rates tend to attract foreign capital, increasing demand for that currency and pushing its value up.
  2. Inflation — Countries with lower inflation rates generally see their currency appreciate over time, as purchasing power remains stronger.
  3. Economic data — Employment figures, GDP growth, trade balances, and manufacturing output all signal economic health. Strong data typically strengthens a currency.
  4. Political stability — Uncertainty, elections, or geopolitical tension can cause a currency to weaken as investors seek safer alternatives.
  5. Market sentiment — Sometimes pure speculation and investor mood ("risk-on" vs. "risk-off") can shift rates significantly in short periods.

The Spot Rate vs. The Rate You Actually Get

The spot rate (or interbank rate) is the "real" exchange rate at any given moment — the rate banks use when trading with each other. This is what you see quoted on Google or financial news sites.

However, the rate you receive as a consumer is almost always different. Banks, bureaux de change, and even many transfer services add a markup — sometimes called a margin or spread — on top of the spot rate. This is how they make money on FX transactions.

For example, if the spot rate is 1.25, your bank might offer you 1.18, pocketing the difference. Always compare the rate you're being offered against the real mid-market rate to understand the true cost of your transaction.

Bid and Ask: The Two Sides of Every Quote

Every currency quote has two prices:

  • Bid price — the rate at which the market (or your provider) will buy the base currency from you.
  • Ask price — the rate at which the market will sell the base currency to you.

The difference between the two is called the spread. A tighter spread means a more competitive deal for you.

Key Takeaways

  • Exchange rates reflect the relative value of two currencies against each other.
  • Rates are influenced by interest rates, inflation, economic data, and sentiment.
  • The rate you see online is the interbank (mid-market) rate — not what most providers offer.
  • Always check for hidden markups in addition to stated fees.

With these fundamentals in place, you're better equipped to evaluate currency services, time your transfers, and avoid paying more than necessary every time you cross a border financially.