1. A method of calculating a fee for an online financial transaction, the method comprising: receiving a fee calculation request linked to an online financial transaction associated with a fee type, a country code, and a client identifier; selecting, using a microprocessor, an initial base fee from either a default base fee determined by the fee type and the country code or from an overriding base fee associated with the financial transaction, wherein the initial base fee includes a transaction percentage and a fixed amount; and applying, using the microprocessor, at least one adjustment to the initial base fee to calculate a final fee, the at least one adjustment being applied when an associated condition set is determined to be true.