Common Metric Sizes of Allen™ Keys

1.3 mm	= 0.051"
1.5 mm	= 0.059"
2 mm	= 0.079"
2.5 mm	= 0.098"
3 mm	= 0.118"
3.5 mm	= 0.138"
4 mm	= 0.157"
4.5 mm	= 0.177"
5 mm	= 0.197"
6 mm	= 0.236"
7 mm	= 0.275"
8 mm	= 0.315"
9 mm	= 0.354"
10 mm	= 0.394"
11 mm	= 0.433"
12 mm	= 0.472"

Common SAE Sizes of Allen™ Keys

	= 0.050"
1/32 in	= 0.031"
3/64 in	= 0.047"
1/16 in	= 0.0625"
5/64 in	= 0.078"
3/32 in	= 0.094"
7/64 in	= 0.109"
1/8 in	= 0.125"
9/64 in	= 0.141"
5/32 in	= 0.156"
3/16 in	= 0.188"
7/32 in	= 0.219"
1/4 in	= 0.250"
5/16 in	= 0.3125"
3/8 in	= 0.375"
7/16 in	= 0.4375"
1/2 in	= 0.500"
9/16 in	= 0.5625"
5/8 in	= 0.625"