Cross Rate Calculator
Multiply A/B by B/C and the B cancels, leaving A/C. If one B costs 1,380 of A and one C costs 1.08 of B, then A per C is 1,490.4. A real conversion walks that chain twice, so the spread lands twice too: 1% on each leg makes it 1.0201×, or about 1,520.4 as the rate you actually pay.
Your numbers
A per C
1,490.4
C per A
0.000671
Rate after both spreads
1,520.357
Formula
A per C = A per B × B per C
Two 1% legs cost 2.01%, not 2%. The gap is small, but where the pair is quoted directly, not routing through a third currency is usually cheaper. To see the hidden fee on a single leg, use the exchange-spread page.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| A per BHow much A one unit of B costs — enter the quoted rate as it stands. | 1,380 | 0 and up |
| B per CHow much B one unit of C costs; the two B figures cancel out. | 1.08 | 0 and up |
| Spread (%)The gap between mid-market and what you got — the hidden fee. | 1 | 0 ~ 20 |
Step by step
Quick reference table
Results when only A per B changes and everything else stays put.
| A per B | A per C | C per A | Rate after both spreads |
|---|---|---|---|
| 690 | 745.2 | 0.001342 | 760.1785 |
| 1,035 | 1,117.8 | 0.000895 | 1,140.2678 |
| 1,380 | 1,490.4 | 0.000671 | 1,520.357 |
| 2,070 | 2,235.6 | 0.000447 | 2,280.5356 |
| 2,760 | 2,980.8 | 0.000335 | 3,040.7141 |
What each result means
| Result | At default values |
|---|---|
| A per CThe A-to-C rate you get by chaining the two quotes. | 1,490.4 |
| C per AHow much C one unit of A costs — the reciprocal of the A/C rate. | 0.000671 |
| Rate after both spreadsThe rate you really pay once a spread is taken on each of the two legs. | 1,520.357 |
Common mistakes
Two 1% legs cost 2.01%, not 2%. The gap is small, but where the pair is quoted directly, not routing through a third currency is usually cheaper. To see the hidden fee on a single leg, use the exchange-spread page.
Glossary
- A per B
- How much A one unit of B costs — enter the quoted rate as it stands.
- B per C
- How much B one unit of C costs; the two B figures cancel out.
- Spread
- The gap between mid-market and what you got — the hidden fee.
- A per C
- The A-to-C rate you get by chaining the two quotes.
- C per A
- How much C one unit of A costs — the reciprocal of the A/C rate.
- Rate after both spreads
- The rate you really pay once a spread is taken on each of the two legs.
Frequently asked questions
Q. How is Cross Rate Calculator calculated?
A per C = A per B × B per C — Multiply A/B by B/C and the B cancels, leaving A/C. If one B costs 1,380 of A and one C costs 1.08 of B, then A per C is 1,490.4. A real conversion walks that chain twice, so the spread lands twice too: 1% on each leg makes it 1.0201×, or about 1,520.4 as the rate you actually pay.
Q. Can you walk through an example?
With A per B 1,380, B per C 1.08, Spread 1%, the answer is A per C 1,490.4.
Q. What do I need to enter?
Enter A per B, B per C, Spread. The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only A per B moves the answer to A per B 690 → A per C 745.2 and A per B 2,760 → A per C 2,980.8. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
Two 1% legs cost 2.01%, not 2%. The gap is small, but where the pair is quoted directly, not routing through a third currency is usually cheaper. To see the hidden fee on a single leg, use the exchange-spread page.
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