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Currency Exchange Conversion

Also known as convert currency · exchange rate calculator · how much is in dollars · foreign exchange conversion · convert money at a rate · fx conversion

B=A rB = A\,r

Units aren’t used in this calculation — every value is a plain number.

Worked example: 250 at a rate of 0.73 → 182.50 — press Try an example to run it live, then adjust anything.

Enter your known values, leave one input blank, and solves for the missing one. Tap a variable’s symbol to see what it means, with a typical value.

See also
Percent of a Number — what the spread between the bank's rate and the mid-market rate costs, as a percentProportion (Solve a/b = c/d) — the same conversion written as two equal ratios, which is how it is taught before the word rate appearsUnit Price (Price per Unit Quantity) — comparing two shelf prices once both are in the same currency

Learning zone

Multiply the amount by the rate. The arithmetic is one line; everything difficult about currency conversion is in knowing which rate and which direction.

A quoted rate always names a direction. If the rate is 0.73 target per source, then 250 of the source becomes 182.50 of the target, and going back the other way means dividing rather than subtracting — the reverse rate is 1/0.73=1.36991/0.73 = 1.3699, not 1−0.731 - 0.73. This is where most of the errors happen, and why this page prints the reciprocal beside any rate it derives.

The rate you are quoted is rarely the rate you get. The mid-market rate is the midpoint between what banks are currently buying and selling at, and it is the number search engines report. A retail conversion sits on one side of it: the spread between the buy and sell quotes is how the conversion is charged, and it is frequently the entire fee even when the transaction is advertised as commission-free. A card that converts at a 3 % spread costs three dollars per hundred whether or not any line on the statement says so. Comparing two providers means comparing the amount that actually lands, not the fee line.

This site holds no exchange rates and never will. Any rate hardcoded into a page is wrong the following day, and a stale rate inside a contract or an invoice calculation is worse than no rate at all — it looks authoritative. The rate is yours to supply, from your bank, your card issuer, or the mid-market quote at the moment the money moves.

Currency Exchange Conversion
B=A rB = A\,r
Where
  • AA= Amount, source currency ($)
  • rr= Exchange rate
  • BB= Amount, target currency ($)
Missing one of these? Work it out first, then come back