How does Backpack calculate its exchange rate? Backpack Support September 13, 2018 11:05 Updated Follow Currently, we are charging BDT84.5/USD. We are charging this amount based on the “HSBC Bangladesh dollar sales rate”. You can see this PDF for reference http://bit.ly/2nMSRo8; here the USD cash sales rate has been taken into account. Related articles Do I have to make payment in advance? How much are you charging for an item? How do I pay for items? Do you deliver items from sites apart from your own or Amazon's? How do I request an item? Comments 0 comments Please sign in to leave a comment.