A method for shoe fitting includes identifying outer foot outlines defining outer boundaries of feet of a user, and inner foot outlines defining weight-bearing areas of the feet in a computer-readable image of the feet. Weighted foot outlines are calculated based on the outer and inner foot outlines. A plurality of unfilled shoes are defined by a common shoe last having a last bottom outline, and sets of different left and right interchangeable insole adapters for insertion into the unfilled shoes are provided. The adapters match the last bottom outline and have respective adapter outlines. The weighted foot outlines are compared with the adapter outlines, to determine an optimal shoe size of a pair of shoes out of the plurality of the unfilled shoes, and to select left and right insole adapters from the sets of the interchangeable insole adapters whose adapter outlines best match the weighted foot outlines.