Interbank Exchange Rate Calculator
Compare the mid-market rate against retail bank markups
Understanding Interbank Exchange Rates
The interbank exchange rate, often referred to as the "mid-market rate," is the wholesale price at which global banks trade currencies with each other. This is the "real" exchange rate you see on Google or financial news networks like Bloomberg and Reuters.
Why Consumers Rarely Get This Rate
When you exchange money at a high-street bank, airport kiosk, or via a credit card, you are rarely given the interbank rate. Instead, providers add a markup or "spread" to the rate. This markup is essentially a hidden fee that makes the exchange less favorable for you.
Calculation Methodology
The math behind currency conversion with markups is straightforward:
- Interbank Value: Amount × Interbank Rate
- Retail Rate: Interbank Rate × (1 – (Markup % / 100))
- Retail Value: Amount × Retail Rate
- Hidden Cost: Interbank Value – Retail Value
Real-World Example
If you are converting 1,000 USD to EUR and the interbank rate is 1.10:
- At the interbank rate, you should receive 1,100.00 EUR.
- If the bank applies a 3% markup, your retail rate becomes 1.067.
- You receive 1,067.00 EUR.
- The "hidden fee" you paid for the convenience is 33.00 EUR.
Note: This calculator assumes the markup is subtracted from the conversion rate (typical for buying foreign currency). Actual bank logic may vary slightly based on "Buy" vs "Sell" side spreads.