Visa – The main currency is the US dollar.
MasterCard – the main currency can be the US dollar and Euro.
When shopping on the Internet, the code CVV2 is used for Visa cards and CVC2 for MasterCard.
Below are some examples of how conversion is performed in different countries.
Your account is in dollars. Are you in the USA:
Visa: USD
MasterCard: USD> EUR> USD
Your account in rubles. You are in Germany:
Visa: RUB> USD> EUR
MasterCard: RUB> EUR
Your account in Euro. You are in Italy:
Visa: EUR> USD> EUR
MasterCard: EUR
Your account in Euro. You are in Paris:
Visa: EUR> USD> EUR
MasterCard: EUR
Your account in rubles. Are you in France:
Visa: RUB> USD> EUR
MasterCard: RUB> EUR
Your account in rubles. You are in Sweden:
Visa: RUB> USD> EUR> SEK or RUB> USD> SEK
MasterCard: USD> EUR> SEK
Hence the conclusion that Visa is better to use in America, MasterCard – in Europe.
See also:
Visa conversion rate
https://usa.visa.com/support/consumer/travel-support/exchange-rate-calculator.html
MasterCard conversion rate
https://www.mastercard.us/en-us/consumers/get-support/convert-currency.html