Great question. We accept donations from all over the world and those donations will be processed in US or Canadian dollars. When you create your fundraiser, you'll choose either the American flag or the Canadian flag and that will designate which currency the donations will be accepted as.
As far as any extra fees an international donor will incur, it all depends on their financial institution. CrowdRise itself does not charge any extra fees on international cards.
An international donor will receive a receipt that contains all of the information the US IRS or Candian CRA requires for a donation receipt. Any other questions about the tax information needed for their country of residence will have to be researched by the individual donor.