A currency converter changes an amount from one currency to another using an exchange rate, here the daily euro reference rates from the European Central Bank. Formula: Converted = amount x rate(from, to). Same currency returns the amount unchanged. On the ECB rates for 21 October 2026, 100 US dollars converts to about 9,446.90 Indian rupees and 100 euros to 112.34 dollars.
On this page
How to use the currency converter
- Enter the amount you want to convert.
- Choose the currency you have in “From” and the one you want in “To”.
- Read the converted amount and the rate for 1 unit.
- Compare it with the rate your bank or transfer provider quotes.
What is the currency converter formula?
- Converted amount = amount × exchange rate (units of the “to” currency per 1 unit of the “from” currency)
- Cross rate between two non-euro currencies = (euro rate of the “to” currency) ÷ (euro rate of the “from” currency)
- If both currencies are the same, the amount is unchanged
The currency converter uses euro foreign exchange reference rates published by the European Central Bank (ECB), fetched through the free Frankfurter service.
Currency converter worked example
ECB reference rates for 21 October 2026: 1 EUR = 1.1234 USD, 0.83825 GBP and 106.1265 INR.
| Conversion | Rate used | Result |
|---|---|---|
| 100 USD to INR | 106.1265 ÷ 1.1234 = 94.4690 | 9,446.90 INR |
| 100 EUR to USD | 1.1234 | 112.34 USD |
| 500 GBP to USD | 1.1234 ÷ 0.83825 = 1.3402 | 670.09 USD |
| 1,000 USD to GBP | 0.83825 ÷ 1.1234 = 0.7462 | 746.17 GBP |
Rates change every working day, so the currency converter will show different figures when you use it.
What the ECB reference rate is
The ECB publishes reference rates for a set of major currencies against the euro once each working day, based on a regular daily concertation between central banks that normally takes place around 14:10 CET. The ECB says the rates are published for information purposes only and that using them for transactions is strongly discouraged. They are close to the mid-market rate, halfway between buying and selling prices, at that moment.
Why your bank gives you a different rate
- Spread: banks and exchange bureaus sell currency above the mid-market rate and buy it below.
- Fees: transfer fees, card foreign transaction fees or commissions are added on top.
- Timing: markets move during the day, while reference rates are fixed once a day.
- Dynamic currency conversion: when a card terminal abroad offers to charge you in your home currency, the rate is often worse; paying in the local currency is usually cheaper.
Check the real cost of a transfer
Compare the amount the recipient will receive, not just the fee. Take the provider’s quoted rate, divide it by the mid-market rate, and the gap is the hidden margin. For example, if the reference rate gives 94.47 INR per USD and a provider offers 92.50, the margin is about 2.1%, or roughly $2.10 on every $100. U.S. consumers sending money abroad get certain disclosures under the CFPB’s remittance transfer rule, including the exchange rate and the amount to be received.
Estimates for education only, not financial advice. Your bank’s or provider’s rate is final.
Timing a currency exchange
Exchange rates move every day, and nobody can reliably predict short-term moves. If you need foreign currency for a trip or a payment, a practical approach is to avoid the worst rates rather than chase the best: do not exchange at airport kiosks or hotel desks, and decline “dynamic currency conversion” when a card terminal abroad offers to charge you in your home currency, as the rate it uses is often poor. For large transfers, splitting the amount over several dates spreads the risk of a bad day.
Use the currency converter to check the mid-market rate before you pay, then compare it with the rate and fees your bank or provider offers. The difference is the real cost of the exchange. Some providers advertise “no fee” but build their margin into a weaker rate, so the currency converter comparison is the only way to see the full cost.
Related converters and calculators
Related calculators:
- VAT calculator: prices abroad
- Percentage calculator: fee margin
- Salary increase calculator UK: pay in pounds
- Inflation calculator: purchasing power
Sources
ECB: Euro foreign exchange reference rates; CFPB: Sending money abroad.
Questions about this calculator
Where do the exchange rates come from?
From the European Central Bank’s daily euro reference rates, via the Frankfurter service.
How often are the rates updated?
Once each working day, normally after the ECB concertation around 14:10 CET.
Is this the rate my bank will give me?
Usually not. Banks add a spread and fees to the mid-market rate.
Can I use ECB rates for a transaction?
The ECB says they are for information only and discourages using them for transactions.
How do I convert between two non-euro currencies?
Divide the euro rate of the target currency by the euro rate of the source currency.
Check the assumptions and units before relying on a result. Financial, tax and health estimates do not replace advice for your individual circumstances.
Report a calculation issue