Magento Open Source 2.2.x

Currency Configuration

Before setting up individual currency rates, you must first set the scope of the base currency, By default, it is set to global, which applies the base currencyThe primary form of currency used in store transactions. setting to the entire store hierarchy. If you have a multisite installation of Magento, you can manage multiple base currencies by setting the scope to the website level.

Then, specify which currencies you accept, and the currency that you want to use for the display of prices in your store. In the following illustration, the scope of the base currency is set at the website level, so each website can have a different base currency.

Scope of Base Currency