Russian currency is Ruble and it is accepted in every shop, supermarket, etc in cash and with using CC.
Credit cards are accepted pretty much everywhere: in hotels, restaurants, and supermarkets (even in smaller towns), so, the money exchange is not that needed, as before. To feel comfortable currency may be exchanged in banks, but not in the big sums. The exchange rate depends on the Bank, but it is more or less equal. The most famous and trustworthy bank in Russia is Sberbank and it has dozens cash machines outdoors in every Russian city.

Tipping is typical in Russian (preferably in cash) in big cities in the amount of 10% from the bill.

Official Exchange rates you can check here

EUR = 90 RUR
USD = 73 RUR
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