Size------------------Insole length(CM)-----------Fit foot length(CM)
2.5 UK / 35 EU --------------22.5-----------------22
3 UK / 36 EU-----------------23--------------------22.5
4 UK / 37 EU-----------------24--------------------23.5
4.5 UK / 38 EU-----------------24.5-----------------24
5 UK / 39 EU--------------25--------------------24.5
6 UK / 40 EU----------------25.5------------------25
7 UK / 41 EU----------------26.5------------------26
8 UK / 42 EU----------------27--------------------26.5
9 UK / 43 EU----------------27.5--------------------27
It is reasonable if the size difference is within 2-3cm.