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Guides · 4 min read

How Currency Conversion Actually Works

Why the exchange rate you see today won't be the exact one tomorrow, and what that means for you.

Where Exchange Rates Actually Come From

Exchange rates aren't set by one single authority — they emerge from currency trading happening constantly across global markets. Central banks (like the European Central Bank) publish daily reference rates based on that market activity, and most conversion tools, including free ones, pull from these official reference rates rather than live trading data.

Why the Rate You See Isn't What You'll Actually Get

If you've ever converted money at a bank or exchange counter and gotten a worse rate than what a converter showed you, this is why: the "mid-market rate" (what converters display) is the raw, no-markup exchange rate. Banks, exchange counters, and payment apps add their own margin on top — sometimes small, sometimes surprisingly large. The mid-market rate is genuinely useful as a reference point, just not the rate you'll receive in a real transaction.

Why Rates Update Daily, Not Constantly

Free reference-rate services typically update once a day (often around mid-afternoon Central European Time, tied to the ECB's daily publication). This is different from live trading platforms that update every second — for everyday purposes like budgeting a trip or checking roughly how much something costs, a daily rate is more than precise enough.

A Practical Tip

If you're sending money internationally or exchanging cash, use a converter to know the fair reference rate first — then compare that against what your bank or service is actually offering. A gap of 1-2% is normal; anything much larger is worth shopping around for a better option.

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