How to use the currency calculator
On the Live exchange rate tab, enter an amount and choose the currency you have and the one you want. The result shows the converted amount, the rate in both directions and the time of the rates. Clear Popular currencies only to choose from all 161 currencies in the list, and use Swap currencies to convert the other way. On the Custom rate tab, enter any rate you were offered and the amount to convert.
Currency conversion formula
An exchange rate is the price of one currency in another. With a rate of R units of currency B per 1 unit of currency A, amount in B = amount in A × R and amount in A = amount in B ÷ R. The rate the other way is 1 ÷ R.
Currency conversion example
With the custom rate of 4 B per 1 A, 100 A converts to 100 × 4 = 400 B, and 100 B converts back to 100 ÷ 4 = 25 A. One unit of B is worth 0.25 A.
Cross rates
Rates between two currencies are found through a common one, usually the U.S. dollar. If 1 dollar buys 0.92 euros and 150 yen, then 1 euro buys 150 ÷ 0.92 = 163.04348 yen. The live calculator works this way: it gets every rate per 1 dollar and divides the two you choose.
Mid-market rate and the rate you get
The live calculator uses mid-market rates, the midpoint between what buyers pay and sellers ask, updated once a day. Banks, exchange offices and card networks add a margin on top. Say the mid-market rate is 0.92 euros per dollar and a bank offers 0.89: 1,000 dollars buy 890 euros instead of 920, a hidden fee of 3.26%. To see what you will really receive, enter the offered rate on the Custom rate tab.
| Margin | Rate offered | You receive | Lost to the margin |
|---|---|---|---|
| 0.5% | 0.9154 | 915.4 EUR | 4.6 EUR |
| 1% | 0.9108 | 910.8 EUR | 9.2 EUR |
| 2% | 0.9016 | 901.6 EUR | 18.4 EUR |
| 3% | 0.8924 | 892.4 EUR | 27.6 EUR |
| 5% | 0.874 | 874 EUR | 46 EUR |
For 1,000 dollars at a sample mid-market rate of 0.92 euros per dollar.
Currency conversion in Excel
With the amount in A1 and the rate in B1, =A1*B1 converts the amount and =A1/B1 converts it back. For the example, A1 = 100 and B1 = 4 return 400 and 25. For a cross rate, divide the two rates per dollar: =150/0.92 returns 163.04348.
Tips for exchanging money
- Compare the offered rate with the mid-market rate: the difference is the hidden fee.
- Airport and hotel exchange desks usually have the widest margins.
- When paying by card abroad, choose to pay in the local currency rather than in your own.
- Cards with no foreign transaction fee save the fee of up to about 3% that many cards charge on every purchase.
Related calculators
To see how much buying power a currency loses over time, use the inflation calculator. The sales tax calculator adds U.S. state and city tax to a price, and the percentage calculator finds the percent difference between two rates.