Cross Rate Calculator
The interactive calculator loads here. It uses the mid-market rate (30 Sept 2026, European Central Bank reference data) or the live rate when available.
What a cross rate is
Most exchange rates are quoted against one big currency, usually the US dollar or the euro. The rate between two other currencies, say the euro and the Japanese yen, is a cross rate: it is worked out from each currency's quote against that common currency. The European Central Bank publishes its reference rates this way, all against the euro, and notes that rates between any two other currencies are derived from them. If 1 C = a units of A and 1 C = b units of B, then 1 A = b ÷ a units of B.
Worked example
Suppose 1 US dollar = 0.90 euros and 1 US dollar = 150 yen. The euro-yen cross rate is 150 ÷ 0.90 = 166.67 yen per euro, and 1 yen = 0.006 euros. Converting €1,000 at that cross rate gives ¥166,667. If your bank instead converts euros to dollars and then dollars to yen, taking a 1% spread on each leg, you get €1,000 ÷ 0.90 × 0.99 = $1,100, then $1,100 × 150 × 0.99 = ¥163,350. The double conversion costs ¥3,317, or 1.99%, because the two spreads compound: 1 − 0.99 × 0.99 = 0.0199.
When this matters
- Paying a supplier or receiving income in a currency your bank does not quote directly, where the bank routes through dollars or euros.
- Checking whether a card or money transfer provider's rate between two non-dollar currencies is fair.
- Receiving money in one foreign currency and spending it in another, such as a salary in pounds spent in Thailand.
- Reading financial news that quotes everything in dollars, when you need the rate between two other currencies.
Leave the quote fields blank to use today's mid-market rates, or type in the rates your bank shows to see the cross rate it is really giving you. The markup calculator then shows how far any quote is from the mid-market rate.
Frequently asked questions
How do you calculate a cross rate?
Divide the two quotes against the common currency. If 1 USD = 0.90 EUR and 1 USD = 150 JPY, then 1 EUR = 150 ÷ 0.90 = 166.67 JPY.
Why are cross rates usually worse at a bank?
Banks often convert through the dollar or euro in two steps and take a spread on each, so the costs compound. Two 1% spreads cost 1.99% overall, not 1%.
Which common currency should I use?
Any currency quoted against both of yours gives the same mid-market cross rate. Use the one your bank or provider actually converts through if you are checking their quotes.
Is the cross rate the same as the mid-market rate?
When both quotes are mid-market rates, yes: the cross rate is the mid-market rate between the two currencies. If the quotes include a bank's margin, the cross rate carries both margins.