Bolt Wrench Size (in)

Written by Matt Milbury on . Posted in Flange Bolt Datasheets

Bolt Head Uses Wrench Size (in)

  • *ISO standard
Bolt

Size

Wrench Size
Hex Bolt,

Lag Bolt,andSquare Bolt

Heavy

Hex Bolt

#0 - -
#1 - -
#2 - -
#3 - -
#4 - -
#6 1/4 -
#8 1/4 -
#10 5/16 -
#12 5/16 -
1/4 7/16 or 3/8 -
5/16 1/2 -
3/8 9/16 -
7/16 5/8 -
1/2 3/4 7/8
9/16 13/16 -
5/8 15/16 1 1/16
3/4 1 1/8 1 1/4
7/8 1 5/16 1 7/16
1 1 1/2 1 5/8
1 1/8 1 11/16 1 3/4
1 1/4 1 7/8 2
1 3/8 2 1/16 2 9/16
1 1/2 2 1/4 2 3/4
1 3/4 2 5/8 2 15/16
2 3 3 1/8
2 1/4 3 3/8 3 1/2
2 1/2 3 3/4 3 7/8
2 3/4 4 1/8 4 1/4
3 4 1/2 4 5/8
3 1/4 4 7/8 5
3 1/2 5 1/4 5 3/8
3 3/4 5 5/8 5 3/4
4 6 6 1/8

Bolt Head Uses Wrench Size (mm)

Bolt

Diameter

Wrench Size
ANSI/ISODINJISDIN/ISP

Heavy Hex

4 7 7 7 -
5 8 8 8 -
6 10 10 10 -
7 - 11 - -
8 13 13 12 -
10 16 17 14 -
12 18 19 17 22/21*
14 21 22 19 -
16 24 24 22 27
18 - 27 - -
20 30 30 - 34/32*