Convert currencies using preset rates or your own exchange rate and fee assumptions.
This tool provides estimates for informational purposes only and is not a substitute for professional financial, tax, academic, medical, fitness, or legal advice. Results vary based on your assumptions, rates, region, and provider rules. Always confirm key figures before making decisions.
| Item | Value |
|---|
Currency exchange is something virtually every person encounters — whether booking a holiday, buying products from overseas, sending money to family abroad, or investing in international markets. Yet the mechanics of how exchange rates are set, why different providers offer different rates, and how to get the best deal are poorly understood by most people. This comprehensive guide covers everything from the basics of how exchange rates work to the specific costs charged by UK banks, US providers, and online transfer services.
An exchange rate is the price of one currency expressed in terms of another. The mid-market rate (also called the interbank rate or spot rate) is the midpoint between the buy and sell prices that banks and financial institutions use when trading currencies with each other. It is the "true" rate you see on Google, XE.com, or Reuters — and it is almost never the rate you actually get when exchanging money.
Every provider who sells currency to the public builds in a bid/ask spread and often an additional margin. The bid price is what the provider will buy the currency for; the ask price is what they will sell it for. The difference is their profit. A high-street bank might offer a GBP/EUR rate of 1.14 when the mid-market rate is 1.17 — that 3-cent difference represents approximately 2.6% of the transaction value going to the bank.
Floating exchange rates are determined by supply and demand in the foreign exchange (forex) market, which trades over $7.5 trillion per day globally. The British pound (GBP), US dollar (USD), euro (EUR), and Japanese yen (JPY) all float freely. Their values change every second based on economic data, interest rate decisions, geopolitical events, and trader sentiment.
Fixed (or pegged) exchange rates are maintained by a government or central bank at a set value against another currency or basket of currencies. The Hong Kong dollar is pegged to the USD at approximately 7.75–7.85. Saudi Arabia pegs the riyal to the USD at 3.75. Many smaller economies peg their currencies to provide stability for trade.
| Pair | Nickname | Daily Volume (approx.) |
|---|---|---|
| EUR/USD | The Euro | ~$1.1 trillion |
| USD/JPY | The Ninja | ~$550 billion |
| GBP/USD | Cable | ~$340 billion |
| USD/CHF | The Swissie | ~$240 billion |
| GBP/EUR | The Chunnel | ~$100 billion |
GBP/USD is nicknamed "Cable" because the exchange rate was historically transmitted between London and New York via a transatlantic telegraph cable laid in 1858.
The British pound has experienced dramatic swings against the US dollar in recent history. In the period leading up to the 2016 Brexit referendum, GBP/USD traded around 1.45–1.50. On the night of the Brexit vote result (24 June 2016), sterling crashed to 1.32 — its biggest single-day fall since the 1985 Plaza Accord. By October 2016, it had fallen further to 1.20.
The most dramatic moment came in September 2022 when the Truss government's "mini-Budget" sent GBP/USD to an all-time low of approximately 1.035 — terrifyingly close to parity with the US dollar for the first time in history. The pound has since recovered to around 1.25–1.30 as of 2024.
For UK travellers and those converting pounds to dollars, this volatility matters enormously. Converting £10,000 at 1.50 yields $15,000. The same conversion at 1.03 yields only $10,300 — a difference of nearly $4,700.
Most currency exchange providers make money by offering rates worse than the mid-market rate. The typical margin added above the interbank rate varies by provider:
| Provider Type | Typical Margin Over Mid-Market | Additional Fees |
|---|---|---|
| High-street bank (UK) | 3–5% | Often £0–£25 transfer fee |
| US bank (wire transfer) | 3–4% | $25–$50 wire fee |
| Airport bureau de change | 8–15% | May also charge commission |
| Post Office (UK) | 2–4% | None for click and collect |
| Wise (TransferWise) | 0.35–1% | Transparent low fixed fee |
| Revolut / Starling | 0% on weekdays (limits apply) | Weekend markup of ~1% |
| PayPal | 3–4% | Additional transaction fees |
Wise was founded in 2011 with the explicit mission of offering the mid-market rate with a small, transparent fee. Unlike banks that hide their profit in the exchange rate, Wise charges a percentage fee (typically 0.35–1% depending on the currency pair and amount) and provides the real mid-market rate. For a £10,000 transfer to USD, Wise might charge £35–£100 versus a bank potentially taking £300–£500 in hidden spread. Wise is regulated by the FCA in the UK and FinCEN in the US.
Purchasing Power Parity (PPP) is an economic theory stating that in the long run, exchange rates should adjust so that identical goods cost the same in different countries. The Big Mac Index, invented by The Economist magazine in 1986, uses the price of a McDonald's Big Mac as a proxy. If a Big Mac costs $5.58 in the USA and £4.49 in the UK, the implied PPP exchange rate is 4.49/5.58 = 0.80 GBP/USD, suggesting the pound is overvalued if the market rate is 1.27.
| Currency | ISO Code | Symbol |
|---|---|---|
| British Pound | GBP | £ |
| US Dollar | USD | $ |
| Euro | EUR | € |
| Japanese Yen | JPY | ¥ |
| Swiss Franc | CHF | Fr |
| Canadian Dollar | CAD | CA$ |
| Australian Dollar | AUD | A$ |
| Indian Rupee | INR | ₹ |
Global remittances — money sent by migrants back to their home countries — totalled approximately $860 billion in 2023 (World Bank estimate). The UK is a major remittance hub, with large communities sending money to India, Pakistan, Nigeria, and the Philippines. The global average cost of sending $200 is around 6%, but this varies enormously. Bank transfers remain the most expensive corridor; mobile money services and dedicated remittance operators like Wise, Remitly, and WorldRemit typically cost 1–3%.
SWIFT (Society for Worldwide Interbank Financial Telecommunication) is the messaging network used for international bank transfers. SWIFT transfers typically take 1–5 business days and involve correspondent bank fees that can add $10–$50 per transfer on top of the exchange rate spread. Local bank transfers (such as SEPA in Europe, Faster Payments in the UK, or ACH in the US) are faster and cheaper but only work within specific regions.
Some people use cryptocurrency (particularly stablecoins like USDT or USDC) as a mechanism for cross-border value transfer. The theory is that converting GBP to USDT, sending to the recipient, and converting to USD avoids traditional banking fees. In practice, the buy/sell spread on crypto exchanges, network transaction fees (gas fees), and regulatory complexity often make this more expensive and slower than Wise for standard amounts. Cryptocurrency exchanges in the UK must be registered with the FCA for AML/KYC compliance.
The mid-market rate (also called the interbank rate or spot rate) is the midpoint between the buying and selling prices in the wholesale foreign exchange market. It is the "true" exchange rate you see on Google or XE.com. Banks and exchange providers add a margin on top of this rate when selling currency to consumers — typically 2–5% for banks, and as low as 0.35% for providers like Wise.
UK high-street banks typically add a margin of 3–5% over the mid-market rate when exchanging currency. On £1,000, this means you receive approximately £30–£50 less value than at the mid-market rate. Some banks also charge a fixed transaction fee of £5–£25. Using a specialist service like Wise or Revolut can reduce the cost to 0.35–1%.
GBP/USD fell sharply from around 1.45–1.50 before the June 2016 Brexit referendum to approximately 1.20 by October 2016 — a fall of nearly 20%. The pound hit an all-time low of around 1.035 in September 2022 following the Truss government mini-Budget, before recovering to 1.25–1.30 in 2023–2024.
Yes. Wise is authorised and regulated by the Financial Conduct Authority (FCA) in the UK (reference 900507) and registered with FinCEN in the US. Customer funds are safeguarded in segregated accounts at top-tier banks. Wise uses the real mid-market rate and charges a transparent fee of 0.35–1%, making it consistently cheaper than banks for international transfers.
Currency markets are most liquid and spreads are tightest during overlapping trading sessions — particularly when both London and New York markets are open (1pm–5pm GMT). Avoid exchanging at weekends when some providers (including Revolut) charge a markup because the interbank market is closed. Major economic announcements (such as US NFP jobs reports or Bank of England decisions) can cause sharp rate moves.
SWIFT (Society for Worldwide Interbank Financial Telecommunication) is the global messaging network that banks use to communicate international transfer instructions. A SWIFT transfer typically takes 1–5 business days and may involve correspondent bank fees of $10–$50 that are deducted in transit. Faster alternatives include SEPA (for European transfers), UK Faster Payments, and specialist services like Wise that use local payment rails.
ISO 4217 is the international standard defining three-letter currency codes. The first two letters generally correspond to the country code (ISO 3166) and the third to the currency name. For example: GBP = Great Britain Pound, USD = United States Dollar, EUR = Euro (uses XU prefix historically). These codes are used in banking systems, invoices, and all financial transactions globally.
The Big Mac Index, created by The Economist in 1986, uses the price of a McDonald's Big Mac to compare purchasing power across countries. If a Big Mac costs $5.58 in the US and £4.49 in the UK, the implied PPP exchange rate is £0.80 per dollar. If the actual exchange rate is £0.79, sterling is approximately 1% overvalued relative to PPP. While simplistic, it captures real-world price differences and has proven remarkably accurate in predicting long-term currency trends.