The length of the jacket is usually proportional to your height and sleeve length, as follows:

Fitting  
34"  36" 38" 40" 42" 44" 46" 48" 50"
Extra Short Crown To Cuff
21 1/2 22 22 1/2 23 23 23 1/2 23 1/2 24 24
Height Jacket Length
28 1/2 29 29 1/2 30 30 1/2 30 1/2 31 31 31

Below 5'6"

    
     
Short Crown To Cuff
22 1/2 23 23 1/2 24 24 24 1/2 24 1/2 25 25
Height Jacket Length
29 29 1/2 30 30 1/2 31 31 31 1/2 31 1/2 31 1/2
5'6" to 5'9"    
     
Regular Crown To Cuff
23 1/2 24 24 1/2 25 25 25 1/2 25 1/2 26 26
Height Jacket Length
29 1/2 30 30 1/2 31 31 1/2 31 1/2 32 32 32
5'9" to 6'0"    
     
Long Crown To Cuff
24 1/2 25 25 1/2 26 26 26 1/2 26 1/2 27 27
Height Jacket Length
30 30 1/2 31 31 1/2 32 32 32 1/2 32 1/2 32 1/2
6'0" to 6'3"    
     
Extra Long Crown To Cuff
25 1/2 26 26 1/2 27 27 27 1/2 27 1/2 28 28
Height Jacket Length
30 1/2 31 31 1/2 32 32 1/2 32 1/2 33 33 33
Above 6'3"    


 

UK/USA size to EU size conversion chart

UK/USA Size 34 36 38 40 42 44 46 48 50
EU Size 44 46 48 50 52 54 56 58 60
Cm 86 91 97 102 107 112 117 122 127