What is Base Currency?
Updated October 20, 2026
The base currency is the first currency in a pair, the one you're buying or selling.
In EURUSD, the euro is the base. The price shows how many dollars one euro costs.
When you buy, you're buying the base and selling the quote.
Lot sizes are measured in the base currency.
Example
EURUSD at 1.0850 means 1 euro costs 1.085 dollars.
Questions people ask
Which one is base in USDJPY?
The US dollar.
Why does it matter?
It tells you what you're actually buying.
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