Calculating trading volume in forex refers to the amount of base currency a trader is trading.
The formula for trading volume on the forex market is:
Trading Volume (TV) = Number of lots x Contract size
Example 1:
An order to buy 3 lots of EURUSD:
TV = 3 x 100,000 EUR
TV = 300,000 EUR
Example 2:
An order to sell 3 lots of UKOIL:
TV = 3 x 1,000 BBL
TV = 3,000 BBL
Note: Trading volume is always calculated in the base currency.