How to use the currency converter
- Wait for the rates to load; the note under the form then shows when they were published.
- Choose the currency you have in From and the one you want in To.
- Type the amount with a dot as the decimal separator and no thousands separators, such as 1250.50, and press Convert.
- Read the result and the calculation line under it, which repeats the amount and shows the exchange rate used for one unit. Swap reverses the pair.
The list has 169 entries: national and territorial currencies, plus a few units that belong to no country: the IMF's Special Drawing Rights (XDR), bitcoin (BTC), and gold, silver, platinum and palladium priced per troy ounce (XAU, XAG, XPT, XPD). If the rate provider has no current rate for one of them, the converter says so instead of guessing.
Where the rates come from
Rates are supplied by Open Exchange Rates, which blends buy and sell prices from several sources and describes its figures as generally the midpoint between the most common buy and sell prices. They are reference rates, not live quotes. The provider publishes new figures periodically, and our server keeps each set it downloads for up to an hour before asking for a fresh one. The page loads the rates once, when it opens, so reload it if it has been open for a long time.
Always check the note under the form that starts with "Rates as of". It gives the date and time the provider published the rates in use, in UTC, so you know exactly how old the figures are.
How the conversion is calculated
The provider quotes every currency against the US dollar: how many units of it one dollar buys. A conversion between two other currencies is a cross rate through the dollar. The rate from currency A to currency B is the number of B per dollar divided by the number of A per dollar, and the result is the amount multiplied by that rate.
With made-up numbers: if one dollar buys 4 units of currency A and 10 units of currency B, then one unit of A is worth 10 ÷ 4 = 2.5 units of B, and 200 A converts to 200 × 2.5 = 500 B. The same calculation, with the published rates, runs when you press Convert. The rate in the calculation line is shown with up to 12 significant digits, and the result is rounded to the decimal places of the target currency.
Decimal places by currency
Not every currency has cents. The converter asks your browser's internationalisation data how many decimals a currency uses and rounds the result to that many. The table shows how an amount of 1234.5 is written in some common currencies:
| Code | Currency | Decimals | 1234.5 is shown as |
|---|---|---|---|
| USD | United States dollar | 2 | 1234.50 |
| EUR | Euro | 2 | 1234.50 |
| GBP | British pound | 2 | 1234.50 |
| JPY | Japanese yen | 0 | 1235 |
| KRW | South Korean won | 0 | 1235 |
| CLP | Chilean peso | 0 | 1235 |
| BHD | Bahraini dinar | 3 | 1234.500 |
| KWD | Kuwaiti dinar | 3 | 1234.500 |
For a few currencies, browsers disagree: the Hungarian forint and the Indonesian rupiah get no decimals in current Chrome but two in some other environments. Bitcoin (BTC), the precious metals (XAU, XAG, XPT, XPD) and Special Drawing Rights (XDR) are not national currencies, so they are shown with up to 12 significant digits instead: a small amount of bitcoin such as 0.00001234 BTC stays visible rather than rounding to 0.00.
What the result does and does not tell you
A midpoint rate is a fair reference for comparing prices, budgeting a trip or estimating what an invoice in another currency is worth today. It is usually not the rate you get when you pay by card, withdraw cash abroad or send money: the company handling the exchange sets its own buy and sell rates and may add charges, so the amount you actually pay or receive is often less favourable. When an invoice, contract or tax return must use a particular official or agreed rate, use that rate rather than this converter.
This tool is not meant for trading decisions. Open Exchange Rates itself says its rates should not be used for precise foreign exchange trades.
Common pitfalls
- Formatted amounts.
1,250.50and1250,50are not read as numbers; the converter asks you to enter an amount. Remove the thousands separator and use a dot for decimals. - Round trips. Converting a result back does not always return exactly the starting amount, because each result is rounded to the target currency's decimals.
- Stale figures. Rates move during the day, and a page left open keeps the rates it loaded. Compare the time in the note with the current time before relying on a result.
Frequently asked questions
Why is my card statement different from this result?
The company that processes a card payment applies its own exchange rate, set when it handles the transaction, and may add charges. The converter shows a reference midpoint rate at the time given in the note.
How often are the rates updated?
Our server requests new rates from the provider at most about once an hour. The note under the form always shows the publication time of the rates you are using.
Can I convert negative amounts?
No. Negative amounts are rejected. To convert a refund or a debt, convert the positive amount and keep the sign yourself.
Why does a currency say that no exchange rate is available?
The list is fixed, but the provider's data changes: a currency can be withdrawn or replaced, as when a country adopts another currency. When no rate is published for a code, the converter reports it rather than showing a wrong number.