Currency Converter

An exchange rate is the price at which one currency can be exchanged for another. When you see a rate quoted as GBP/USD = 1.27, it means one British pound buys 1.27 US dollars. Exchange rates are expressed as currency pairs: the first currency listed (the 'base currency') is the one you are buying or selling, and the second (the 'quote currency') is the one you are using to pay. The rate tells you how many units of the quote currency one unit of the base currency will buy. Rates can also be inverted: if GBP/USD = 1.27, then USD/GBP = 1/1.27 = 0.787, meaning one US dollar buys 0.787 pounds.

Exchange rates in the interbank market — where large financial institutions trade currencies among themselves — are determined by supply and demand, just like any other market price. When there is high demand for a currency relative to its supply, its price rises (it 'appreciates' against other currencies). When supply exceeds demand, it falls (it 'depreciates'). Unlike stock markets with fixed trading hours, the foreign exchange market operates 24 hours a day, five days a week, spanning time zones from Sydney through Tokyo, London, and New York. This continuous operation means rates can move at any time in response to global events.

Most countries now operate under a floating exchange rate system, where the rate is determined freely by market forces without direct government intervention. A smaller number of currencies are pegged — either to a major currency like the US dollar or to a basket of currencies — meaning the central bank actively buys or sells its own currency to maintain the rate within a target band. Hong Kong's dollar has been pegged to the US dollar since 1983, for instance. Managed float systems sit between the two extremes: the rate floats but central banks occasionally intervene to smooth excessive volatility or prevent the rate from moving too far from policy targets.

When a bank or currency dealer quotes an exchange rate, they actually provide two prices simultaneously: the bid price and the ask (or offer) price. The bid is the price at which the dealer will buy the base currency from you; the ask is the price at which they will sell the base currency to you. The ask is always slightly higher than the bid. The difference between the two is called the spread, and it represents the dealer's gross profit margin on the transaction. If GBP/USD bid is 1.2695 and ask is 1.2705, the spread is 10 pips (a 'pip' being the smallest standard price increment, typically 0.0001 for most currency pairs).

The mid-market rate is the exact midpoint between the bid and ask prices. It is the rate you see on financial data providers like Reuters, Bloomberg, and Google Finance. No retail customer actually transacts at the mid-market rate — it is purely a reference benchmark. When your bank charges a 2% margin on a currency conversion, they are applying a spread around the mid-market rate, meaning the rate they offer you is worse on each side. The mid-market rate's value is as a benchmark: by comparing any quote you receive against it, you can immediately quantify exactly how much the spread is costing you.

Spreads vary significantly by currency pair and by the type of institution providing the quote. Major pairs involving the US dollar, euro, pound, and yen — which account for the vast majority of global trading volume — typically have the tightest spreads because of their high liquidity. Exotic pairs involving currencies from smaller or less stable economies have wider spreads because fewer market participants are willing to hold those currencies, making it harder for dealers to offset their exposure quickly. In consumer forex channels, airport kiosks and hotel desks routinely charge spreads of 5-10% or more, while specialist online money transfer services typically operate on 0.5-1.5% spreads for major currencies.

Exchange rates respond to a broad range of economic, political, and psychological factors, often simultaneously. Interest rate differentials between countries are among the most powerful drivers: higher interest rates attract international capital because investors can earn more by holding assets denominated in that currency. When the US Federal Reserve raises interest rates faster than the European Central Bank, demand for US dollar-denominated assets typically rises, pushing the dollar higher against the euro. This relationship — known as interest rate parity in its theoretical form — is one of the most closely watched dynamics in the forex market.

Inflation is another fundamental driver. A country with persistently higher inflation than its trading partners will generally see its currency depreciate over time. Higher inflation erodes the purchasing power of a currency, making the goods and services it buys progressively more expensive in relative terms. This is captured in the theory of purchasing power parity (PPP), which holds that exchange rates should adjust over the long run so that the same basket of goods costs the same in all countries when expressed in a common currency. PPP is a poor predictor of short-term exchange rate movements but a useful framework for understanding long-term trends and assessing whether a currency is fundamentally over- or undervalued.

Trade balances, geopolitical events, and market sentiment can all cause sharp short-term rate movements that defy longer-term fundamentals. A country running a large trade surplus — exporting more than it imports — generates persistent foreign demand for its currency, which tends to appreciate over time. Political uncertainty, elections, referenda, and international conflicts can cause rapid currency moves as investors reassess risk. The British pound fell sharply following the Brexit referendum result in June 2016, losing over 10% against the dollar in hours, as markets priced in the economic uncertainty of the UK leaving the European Union. Sentiment and positioning can also move markets independently of economic fundamentals.

The mid-market rate — also known as the interbank rate or spot rate — is the theoretical midpoint between the buy and sell prices in the wholesale forex market. It is the rate that appears on Google Finance, XE.com, and financial news services. It is a genuine reference price, but it is the rate at which large financial institutions trade with each other in the interbank market. Retail customers — individuals and small businesses — are not able to access this rate. Any provider quoting you the mid-market rate is almost certainly applying additional fees elsewhere in the transaction.

The retail rate is what you actually receive when converting currency through a bank, money transfer service, travel card, or currency exchange kiosk. The gap between the mid-market rate and the retail rate represents the provider's margin and any explicit fees. A high-street bank might mark up the mid-market rate by 3-5% for retail foreign currency purchases. Specialist online money transfer services like Wise typically operate closer to the mid-market rate, charging a transparent fee of 0.5-1.5% of the converted amount. Airport kiosks frequently charge the widest margins of all, sometimes 8-12% above the mid-market rate — which on a $500 conversion amounts to $40-$60 in hidden cost.

The practical implication is that you should always use a mid-market rate tool to establish the true reference rate before obtaining any retail quotes, then calculate the effective cost of each provider's offer as a percentage of the mid-market rate. Our currency converter provides the mid-market rate so you can do exactly this. When comparing providers, look at the total cost of the transaction including all fees — not just the exchange rate offered — since some providers charge a low spread but a high flat fee (which is expensive on small transfers) while others do the reverse. The cheapest option depends on both the size of the transfer and the currency pair.

The single most effective way to minimise currency conversion costs is to avoid converting at the point of travel when you have the least time and negotiating power. Planning currency needs in advance and using a specialist money transfer service or travel card consistently outperforms last-minute airport or hotel conversions. For regular travellers, a multi-currency travel card from a provider like Wise or Revolut allows you to hold balances in multiple currencies and spend abroad at rates close to the interbank rate with no foreign transaction fees. These cards have transformed the economics of international travel by eliminating the 2-4% foreign transaction fees that traditional bank cards commonly charge.

For large one-off transfers — such as buying property abroad, repatriating earnings, or making a large international purchase — a currency broker rather than a retail bank is almost always the right choice. Currency brokers specialise in large foreign currency transactions and can access near-interbank rates that retail banks cannot match. They may also offer forward contracts, which allow you to lock in today's exchange rate for a transaction that will happen up to two years in the future, protecting against adverse currency moves during that window. On a £200,000 property purchase, a 1% improvement in the exchange rate saves £2,000 — easily justifying the time spent finding a good broker.

Timing currency purchases to take advantage of favourable rate movements is possible but carries risk. If you need to exchange currency by a specific date — because you have a payment due — buying when the rate briefly moves in your favour during the window is reasonable. Trying to time the market over a longer period, however, means accepting the risk that the rate moves against you before your deadline. A practical middle ground is to split a large conversion into two or three tranches over the available time window, averaging the rate achieved rather than betting on a single point. This approach reduces the variance of the rate you obtain without requiring you to predict market movements.