International Shopping by NIB Debit MasterCard?

Assalam-u-alaikum :

I would like to know how much USD to PKR CONVERSION + ANY OTHER BANK CHARGES are deducted when NIB Debit MasterCard when used for ONLINE SHOPPING such as to pay at WWW.ALIEXPRESS.COM ?

The CHEAPEST WAY to pay at WWW.ALIEXPRESS.COM ?

Thanks.

Consult their schedule of charges for foreign transactions.