The familiar number is a conversion offer

Dynamic currency conversion lets a merchant or ATM convert a charge to your home currency. Visa explains that the offer includes an exchange rate and may include additional fees or markup.

Sources[1] Visa

Keep the decision yours

Visa requires both amounts, the conversion rate and markup to be displayed. The provider should not select for you. If details are missing or you feel pressured, Visa advises declining conversion and contacting your issuer.

Sources[1] Visa

Separate all three costs

Our comparison: distinguish DCC markup, issuer foreign-transaction fees and ATM charges. Avoiding the first does not necessarily remove the other two. Keep the receipt showing the currency you selected.

Sources[2] Visa