Currency Converter
Enter an amount and pick two currencies to get today's converted value instantly. The reference date is always shown, and it keeps calculating from saved rates even when you're offline.
Why exchange rates aren't one single number
Every currency pair actually has several different "rates" depending on who is quoting it and why. The number this converter shows is the mid-market rate — the fair, no-markup midpoint between what currency dealers buy and sell at, the same figure you'd see quoted on the news or in a central bank bulletin. It's the right number for planning a trip budget, sanity-checking an invoice, or judging whether a remittance quote is fair. It is not, however, the number your bank, card issuer, or an airport exchange counter will actually hand you, because each of them builds its own markup on top before you see a price.
Reading and using the converter
- Type the amount into the Amount field — digits only, with or without thousands separators.
- Choose the currency you're converting From and the one you want To from the two dropdowns.
- Use the ⇄ swap button to flip the pair instantly instead of reopening both dropdowns.
- Tap a quick-pair chip (USD→EUR, GBP→USD, USD→JPY, USD→INR) to jump straight to a common route.
- Check the small reference date printed under the result — it tells you exactly which day's rate table was used, so you know how fresh the number is before relying on it for anything time-sensitive.
The mid-market rate vs. the "매매기준율" you'll actually be quoted
Banks and exchange counters don't quote one rate — they quote a buying rate and a selling rate straddling the mid-market figure, a gap known as the spread. Korean banks publish this as the 매매기준율 (base settlement rate) each morning, then add their own margin on either side: 현찰 살 때 (cash buying, what you pay to acquire foreign cash) sits above it, 현찰 팔 때 (cash selling, what you receive selling foreign cash back) sits below it. The wider the spread, the worse the deal regardless of how the headline rate looks.
How the conversion is actually calculated
Rates for all 16 supported currencies are stored against a single anchor currency, USD. To convert between any two of them, the tool doesn't look up a direct pair — it bridges through that anchor:
Result = Amount × (rate of "To" per 1 USD ÷ rate of "From" per 1 USD)
This is the same method professional FX desks use to build "cross rates" for pairs that rarely trade directly against each other, such as KRW→JPY or INR→GBP.
Worked examples
Example 1 — direct pair. Converting 500 USD to EUR at a sample rate of 0.92 EUR per USD: 500 × 0.92 = 460.00 EUR. No bridging needed since USD is the anchor currency itself.
Example 2 — cross rate through the anchor. Converting 200,000 KRW to JPY, using sample rates of 1,380 KRW per USD and 155 JPY per USD: first 200,000 ÷ 1,380 = 144.93 USD, then 144.93 × 155 ≈ 22,463 JPY. Neither KRW nor JPY was checked directly against the other — the USD bridge did the work invisibly.
Example 3 — mid-market vs. what you'll actually pay. A traveler converts 1,000 USD to EUR here at 0.92 → 920 EUR. Their card issuer, applying roughly a 2% spread plus a 1% foreign-transaction fee, effectively converts at about 0.92 × 0.97 ≈ 0.892, delivering only about 892 EUR — a gap near 28 EUR that's invisible unless you first check the mid-market baseline.
Typical spread and fee ranges by payment method
| Method | Spread vs. mid-market | Extra fee |
|---|---|---|
| Airport / street cash kiosk | 3% – 8% | Usually none, buried in the rate |
| Bank wire transfer | 1% – 3% | Flat fee, roughly $15–$50 |
| Credit / debit card abroad | 0% – 1% | 0% – 3% foreign transaction fee |
| Fintech transfer app | 0.3% – 1% | Small % or flat, disclosed upfront |
| "Pay in home currency" (DCC) | 3% – 7% | Hidden inside the offered rate |
Common mistakes
- Treating this number as final. It's the fair baseline, not what any specific bank, card, or kiosk will charge you — always compare their quoted rate against it before accepting a deal.
- Ignoring the reference date. For a same-day purchase it barely matters; for a large transfer or an invoice negotiated days apart, relying on a stale rate can misstate the real cost.
- Accepting "Pay in [your home currency]" at a foreign card terminal. That Dynamic Currency Conversion option almost always embeds a worse rate than letting your own card network convert it — choose the local currency instead.
- Forgetting the fee sits on top of the spread. A "zero commission" exchange counter can still be expensive if its quoted buy/sell rate is already several percent off the mid-market figure.
What this tool doesn't do
This is a reference calculator, not a trading terminal: as the FAQ notes, the rate table refreshes once a day from mid-market reference sources, not a tick-by-tick interbank feed, so it shouldn't be used to time an FX trade or a large, rate-sensitive transfer. It also has no visibility into any specific bank's actual spread or fee schedule — use the figure here as the honest, no-markup baseline, then ask your bank or transfer provider for their all-in rate and compare the two before you commit.
Sources & further reading
- Federal Reserve H.10 — official daily foreign exchange rates for major currencies
- Bank of England Statistical Database — published daily spot exchange rates
- Bank for International Settlements — FX market statistics and how interbank pricing works
- ISO 4217 — the standard behind three-letter currency codes like USD and EUR
Frequently asked questions
How often are the exchange rates updated, and where do they come from?
This currency converter refreshes once a day from live mid-market reference rates, with two independent sources for reliability: it tries open.er-api.com first and falls back to the European Central Bank (via Frankfurter). The reference date is always printed under the result, so you can see exactly how current the exchange rate is.
Why is the amount my bank or card shows different from this?
This exchange rate calculator uses the mid-market rate — the midpoint between the buy and sell price, the "real" rate you see on Google or Reuters. Banks, cards and money-transfer apps add a spread and fees on top, so their USD to EUR or USD to INR amount is usually a little worse. Use this number as the fair baseline to judge their offer.
What rate does it use when I'm offline or a source is down?
It never leaves you with a blank screen. If both live sources fail, it falls back to the last rate saved on your device (cached for 24 hours), and if there's none, to a built-in snapshot bundled with the app. Whenever the number isn't live, a clear "Not live — using a saved rate" warning and a Retry button appear, so you're never misled.
Are these live, real-time trading rates?
No — and no free tool should claim to be. These are daily mid-market reference rates, fine for shopping, travel budgets and money transfers. They are not tick-by-tick trading rates, so don't use them for FX dealing or large, time-sensitive transfers.
Is my amount sent to a server?
No. Only the exchange-rate table is fetched; every conversion runs locally in your browser. Nothing you type is uploaded, stored, or shared — no account, no tracking, and it keeps working offline from saved rates.