Prints should be sized to fit either the entire frame (without mat), or the mat's opening. Frame packaging/descriptions at retailers will indicate which print sizes it can hold.
IKEA: HOVSTA frame
IKEA: RIBBA frame
Target: Matted PS Narrow Rounded Gallery Frame
West Elm: Wood Gallery Frames Wheat
Target: Elena Photo Frame - Natural Wood - fits A3 print with mount, or A2 print without mount
This landscape / horizontal photograph of a vibrant path toward sunset meanders through palm trees and jungle. I've added a brushed, distressed edge to the image for a spontaneous and improvised effect.