On August 15, 1971, foreign governments lost the right to exchange their US dollars for gold at $35 an ounce. Every other converter on this site stores fixed factors; this currency converter cannot, because that decision opened the road to rates that move every working day. It covers 164 currencies, fetches a reference rate as soon as it loads, and shows the date of that rate next to the result.
WORKED EXAMPLE: THE FORMULA, WITH AN ILLUSTRATIVE RATE
The converter below replaces 1.14 with the rate of the day and prints that rate and its date.
Currency Converter
Definition: An Exchange Rate Is a Price, Not a Constant
An exchange rate states how many units of one currency buy one unit of another. Converting an amount is a single multiplication: amount times rate. A EUR to USD conversion multiplies the euro amount by the number of dollars that one euro buys on that day, and a GBP to USD conversion does the same with the pound.
The reverse direction needs no second rate. If 1 euro buys 1.14 dollars, then 1 dollar buys 1 ÷ 1.14, about 0.877193 euros. The swap button of the converter applies exactly this inversion, so one rate serves both directions of the same pair.
A meter has a fixed definition; a currency has a market price that changes daily. A rate printed in an article would soon be out of date, which is why the example above uses 1.14 only to show the arithmetic.
History: From the $35 Ounce to Floating Rates
According to the Federal Reserve History essay on the end of gold convertibility, forty-four countries met at Bretton Woods, New Hampshire, in 1944 and agreed to keep their currencies fixed to the dollar, adjustable only in exceptional situations, while the dollar was fixed to gold. Once the system became operational in 1958, dollars held by other countries could be converted to gold at $35 an ounce.
The same essay explains that, over the 1960s, the supply of dollars abroad grew faster than the US gold stock, until foreign-held dollars exceeded the gold available to redeem them. On the evening of August 15, 1971, President Nixon announced the closing of the gold window: foreign governments could no longer exchange their dollars for gold.
A rescue attempt followed. At the Smithsonian Agreement of December 1971, the United States devalued the dollar against gold by about 8.5 percent, to $38 an ounce. It did not hold. On February 12, 1973, the dollar was devalued by a further 10 percent, to $42 an ounce, and within a month nearly all major currencies were floating against the dollar.
Where Today's Rate Comes From
For the currencies the central bank covers, the converter uses a public feed of the euro foreign exchange reference rates of the European Central Bank. They are set through a daily concertation procedure between central banks, normally around 14:10 CET, and published around 16:00 CET on every working day except TARGET closing days. The bank states that these rates are published for information purposes only and strongly discourages their use for transactions. Its last rate for the Russian rouble dates from March 1, 2022. Common pairs such as MXN to USD or AUD to USD come from this feed.
For every other currency, including the Moroccan dirham, the Saudi riyal and Bitcoin, the converter reads an open exchange-rate dataset refreshed daily. That dataset also takes over if the central bank feed does not answer. In both cases, the status line names the feed and the date of the rate.
If neither feed answers, the result stays empty rather than showing an invented figure. The box turns red, the rate field remains editable, and a rate typed by hand is labeled as entered manually, on screen and on the printout.
Current Use: Two Currencies Now Tied to the Euro
Two currencies in the menus no longer float. Croatia adopted the euro on January 1, 2023, and the European Central Bank's page on the Croatian changeover gives the conversion rate as 7.53450 kuna per euro, so 100 euros equal 753.45 kuna and 1 kuna equals about 0.132723 euros.
Bulgaria followed on January 1, 2026. In its press release of July 8, 2025, the European Central Bank reports a conversion rate of 1.95583 lev per euro, which makes 1 lev worth about 0.511292 euros. The converter applies these two fixed rates to the euro rate of the day, so a kuna or a lev amount moves against the dollar exactly as the euro does.
Frequently Asked Questions
How is a currency conversion calculated?
Multiply the amount by the rate. At an illustrative 1.14 dollars per euro, 500 euros give 570 dollars.
How is a conversion reversed?
Divide by the same rate, or press the swap button, which inverts it: 1 ÷ 1.14 is about 0.877193.
Why is a date shown next to the rate?
Both feeds publish once a day, so the date tells which day the rate belongs to.
Can this rate be used for an actual exchange?
No. The central bank publishes its reference rates for information only and discourages their use for transactions; use the rate quoted for the transaction itself.
What happens if no rate loads?
The box turns red and the rate field stays open; a rate typed by hand is labeled as entered manually.
How many decimals does Bitcoin get?
Up to 8, against up to 4 for other currencies.
Method and sources. Rates are fetched as soon as the converter loads: reference rates of the European Central Bank where available, an open daily dataset otherwise, and manual entry if both fail. Only the two currency codes are sent to these services, never the amount. The history comes from two Federal Reserve History essays, the kuna and lev rates from the European Central Bank. Calculations were checked with 30-digit arithmetic.
This converter is provided for general reference. Its rates are reference rates, not quotes for buying or selling currency. Written by Staff Editorial, NumeraHub.