Birkenstock EU to AU Size Guide

EU Size	AU Men's	AU Women's	Footbed Length (mm)	Footbed Width (mm)
35	–	4	225	89
36	–	5	230	91
37	4	6	240	93
38	5	7	245	95
39	6	8	250	97
40	7	9	260	99
41	8	10	265	101
42	9	11	270	102
43	10	12	280	103
44	11	–	285	107
45	12	–	290	109
46	13	–	295	113