The automatically loaded rate is a daily reference rate, not a live tradable quote. Actual consumer conversion usually includes a spread, fee, or both.
Reference rate versus the rate you receive
Central-bank and institutional reference rates are designed for information and comparison. A bank, card network, ATM, remittance provider, or cash exchange can apply its own timing, spread, commission, and fixed fee.
For budgeting, run the reference conversion and then compare it with the provider's final amount. The difference represents the combined effect of pricing and fees.
How often rates update
Frankfurter provides daily exchange-rate data from institutional sources. A weekend or holiday request may return the most recent available business-day rate rather than a new same-day observation.
Foreign-exchange markets can move during the day, so a daily reference figure should not be treated as a guaranteed transaction price.
- Check the displayed rate date.
- Use the manual field for a quoted provider rate.
- Keep both currencies consistent with the selected codes.
- Confirm whether a separate fixed fee applies after conversion.
Using the inverse rate
The main rate shows how many destination-currency units equal one source-currency unit. The inverse shows how many source units equal one destination unit.
Swapping the currency selectors requests the opposite pair and makes it easier to compare quotes that are presented in different directions.
The formula used
Converted amount = original amount × exchange rateThe inverse rate equals 1 ÷ exchange rate. Automatic data comes from Frankfurter's public API; a manually entered rate replaces the reference rate for the current calculation.
Example: converting USD to KRW
Enter $1,000, choose USD as the source and KRW as the destination, and the calculator multiplies the amount by the latest available daily reference rate. For a real card purchase or cash exchange, replace the rate with the provider's quoted rate or account separately for its fee.
Sources and further reading
We use primary educational sources to check terminology and explain how the calculation fits into real financial decisions.
Frankfurter — Exchange rates API documentation↗European Central Bank — Euro foreign exchange reference rates↗