Cross Rate Calculator

Use this cross rate calculator to find the exchange rate between two currencies from their US dollar rates, with the direct rate and its inverse.

What it does

The Cross Rate Calculator derives the exchange rate between two currencies when you only know each one's rate against the US dollar. It divides one dollar rate by the other to give the direct rate between the pair.

Data sources & parameters

This calculator uses standard financial formulas and runs entirely in your browser. It needs no external rate data — your result is computed only from the values you enter above.

We always strive to use the latest data for every variable so our results and reports are as accurate as possible. Even so, errors are possible — you should not rely on this tool or its report alone, and we accept no liability for any decision made based on it.

The formula

cross_rate = rate_a_per_usd ÷ rate_b_per_usd; inverse_cross = rate_b_per_usd ÷ rate_a_per_usd

How it works

Enter how many units of currency A and currency B each equal one US dollar. The tool divides rate A by rate B to give the cross rate (A per B) and flips it for the inverse (B per A).

Where it is used

Pricing a currency pair that has no direct quote
Checking a bank or broker's cross-rate quote
Converting between two non-USD currencies

Worked example

If currency A trades at 1.1 per USD and currency B at 1.25 per USD, the cross rate is … (A per B) and the inverse is … (B per A).

What the cross rate calculator does

Enter how many units of currency A and of currency B each equal one US dollar, and the calculator works out the exchange rate between the two, its inverse, and repeats your first rate for checking. Many currency pairs barely trade directly, so the market prices them through the dollar, which is on one side of most trades and has the most liquid quotes. This calculator does the same arithmetic.

Take each dollar rate from a reliable source such as a central bank reference rate or a market data provider. Both must be quoted the same way, as units of the currency per dollar; if one is quoted as dollars per unit, invert it first.

How a cross rate works

A cross rate is worked out through a common third currency. Divide the per-dollar rate of currency A by that of currency B, and the dollar cancels out, leaving the rate of A against B. Reverse the division to get the inverse. The two are reciprocals and always multiply back to one, so if the cross rate is a little under one, the inverse is a little over one.

Why cross rates matter

Whenever you convert between two currencies other than the dollar, a cross rate is behind the price, whether you are travelling, importing, exporting or investing. Working out the theoretical rate yourself lets you compare it with what a bank or currency exchange quotes. The difference is the margin you are paying, which can be large on a big transfer.

Reading the result

The result is the mid-market rate implied by the two dollar quotes, with no margin. Real quotes include a spread between buying and selling prices and often a fixed fee, so the rate you are offered will be a little worse. Compare the fair rate with a provider's quote to see the spread you are charged, use the inverse when a quote is expressed the other way round, and use fresh dollar rates, because exchange rates move continuously and figures from yesterday may be noticeably off today.

This article is general information only and is not financial advice.

About This Cross Rate Calculator

Use this cross rate calculator to get an instant estimate based on the figures you enter. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.

Frequently asked questions

What is a cross rate?

A cross rate is the exchange rate between two currencies that is worked out through a third, common currency instead of quoted directly. Most cross rates are derived through the US dollar because nearly every currency has a liquid dollar quote, so you can divide one dollar rate by another to price the pair.

How does the cross rate calculator work?

You enter how many units of currency A and currency B each equal one US dollar. The calculator divides rate A by rate B to give the cross rate, which tells you how many units of A one unit of B is worth. It also flips the division to show the inverse rate for the pair.

Why derive a rate through the US dollar?

The dollar is on one side of the large majority of global currency trades, so dollar quotes are the deepest and most reliable. When two currencies rarely trade directly against each other, the market prices them by routing through the dollar, and this calculator reproduces that arithmetic.

What is the inverse cross rate?

The inverse simply reverses the direction of the quote. If the cross rate tells you how many units of A one unit of B buys, the inverse tells you how many units of B one unit of A buys. The two numbers are reciprocals of each other and always multiply back to one.

Does the calculator include fees or spreads?

No. It shows the pure mid-market cross rate implied by the two dollar rates you enter. A bank or broker adds a spread and sometimes a fixed fee on top, so the rate you are actually offered will be a little worse than this theoretical figure.

Is my data kept private?

Yes. The whole calculation runs in your browser. Nothing you enter is uploaded, stored, or shared, so you can check any pair of rates without your figures leaving your device.

About the author

Written and reviewed by

Taha Kheirandish

Economics student and independent researcher

Taha Kheirandish reads tax codes the way other people read maps — to find out where a system actually leads, not where it claims to go.

He is an economics student, and his work here is comparative by design. A pension deferral bonus in Quebec, a commuting allowance in Germany, a rent-increase ceiling in the Netherlands: each is a decision a government made about how money should move, and each reads differently once you set it beside eight others. He builds and checks these calculators across nine markets from primary sources — the regulation rather than a summary of it, the ministry’s own circular rather than a news item quoting it.

That is the editorial standard of the site as well as his habit. Every rate, threshold and bracket here carries the document it was read from and the date it takes effect, and gets re-checked when the law moves rather than when someone happens to notice.

He is a researcher, not a licensed adviser, and nothing on this site is personal financial advice. It is arithmetic done carefully with its sources shown — so that you can check it, and take it to someone who is.

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