Dynamic currency conversion is a process that happens when you travel to another country and use your credit or debit card to make a purchase. When you buy something in a different currency, your bank has to convert the price of that item into your home currency so that they can charge you correctly.
To do this, the bank will use the exchange rate to convert the amount from the foreign currency to your own. However, some merchants may offer to do this conversion for you at the time of the purchase so that you don't have to worry about the exchange rate. This is called dynamic currency conversion.
When you choose dynamic currency conversion, the merchant will convert the price of the item into your home currency using their own exchange rate, which is usually higher than the real exchange rate. This means that you may end up paying more for the item than if you had let your bank do the conversion for you.
It's important to note that dynamic currency conversion is always optional, and you can choose to decline it if you prefer to let your bank handle the conversion. Additionally, some banks may charge a foreign transaction fee if you choose to use dynamic currency conversion, so it's always a good idea to check with your bank before traveling abroad to see what fees may apply.