The total amount of Currency A you wish to exchange.
Cross Rate (A / B):–
Inverse Rate (B / A):–
Converted Amount (Currency B):–
function calculateCrossRate() {
// Get input values
var rateA = parseFloat(document.getElementById('currencyA_USD').value);
var rateB = parseFloat(document.getElementById('currencyB_USD').value);
var amount = parseFloat(document.getElementById('conversionAmount').value);
// Validation
if (isNaN(rateA) || rateA <= 0) {
alert("Please enter a valid rate for Currency A.");
return;
}
if (isNaN(rateB) || rateB <= 0) {
alert("Please enter a valid rate for Currency B.");
return;
}
if (isNaN(amount) || amount < 0) {
alert("Please enter a valid conversion amount.");
return;
}
// Calculation Logic
// Formula: Cross Rate (A/B) = Rate A (vs USD) / Rate B (vs USD)
// This gives how many units of B you get for 1 unit of A
var crossRateAB = rateA / rateB;
// Inverse: How many units of A you get for 1 unit of B
var crossRateBA = rateB / rateA;
// Total converted value
var totalB = amount * crossRateAB;
// Update DOM
document.getElementById('results').style.display = 'block';
document.getElementById('resCrossRateAB').innerHTML = crossRateAB.toFixed(5);
document.getElementById('resCrossRateBA').innerHTML = crossRateBA.toFixed(5);
document.getElementById('resConvertedAmount').innerHTML = totalB.toFixed(2);
}
Understanding Cross Currency Rates
In the world of foreign exchange (Forex), a Cross Currency Rate refers to the currency exchange rate between two currencies, both of which are not the official currency of the country in which the exchange quote is given. More commonly in modern trading, it refers to a currency pair that does not involve the US Dollar (USD).
However, since the US Dollar is the primary reserve currency used for settling global trades, most currencies are quoted against the USD. To find the exchange rate between two non-USD currencies (for example, the Euro and the Japanese Yen), traders must calculate the cross rate derived from their respective USD exchange rates.
How the Calculation Works
This calculator determines the exchange rate between Currency A and Currency B by using a common third currency (the Base Currency, typically USD). The logic uses the principle of triangular arbitrage to ensure pricing consistency.
The mathematical formula used depends on how the rates are quoted:
Formula:Cross Rate (A/B) = (Rate of A vs USD) / (Rate of B vs USD)
Example: If 1 Euro = 1.08 USD and 1 British Pound = 1.25 USD, the cross rate of EUR/GBP is 1.08 divided by 1.25, resulting in 0.864. This means 1 Euro is worth 0.864 Pounds.
Why Use a Cross Rate Calculator?
Calculating cross rates manually can be error-prone due to the number of decimal places involved in Forex pricing. This tool is essential for:
International Business: Companies paying suppliers in a third currency need exact conversion rates to forecast costs.
Travel Planning: Travelers visiting multiple countries can determine the purchasing power of their home currency directly against their destination currency.
Forex Trading: Traders use cross rates to identify arbitrage opportunities where the calculated cross rate differs from the market price.
Interpreting the Results
Cross Rate (A / B): This figure represents how many units of Currency B you can buy with 1 unit of Currency A. If the result is less than 1, Currency A is weaker than Currency B.
Inverse Rate (B / A): This shows the reverse—how many units of Currency A are needed to buy 1 unit of Currency B.