US Nut Size Table

Size Diameter* Height
Hex Nut Machine Screw Nut Hex Nut Jam Nut Nylock Nut Machine Screw Nut
#0 - 5/32" - - - 3/64"
#1 - 5/32" - - - 3/64"
#2 - 3/16" - - 9/64" 1/16"
#3 - 3/16" - - 9/64" 1/16"
#4 - 1/4" - - 9/64" 3/32"
#6 - 5/16" - - 11/64" 7/64"
#8 - 11/32" - - 15/64" 1/8"
#10 - 3/8" - - 15/64" 1/8"
#12 - 7/16" - - 5/16" 5/32"
1/4" 7/16" 7/16" 7/32" 5/32" 5/16" 3/16"
5/16" 1/2" 9/16" 17/64" 3/16" 11/32" 7/32"
3/8" 9/16" 5/8" 21/64" 7/32" 29/64" 1/4"
7/16" 11/16" - 3/8" 1/4" 29/64" -
1/2" 3/4" - 7/16" 5/16" 19/32" -
9/16" 7/8" - 31/64" 5/16" 41/64" -
5/8" 15/16" - 35/64" 3/8" 3/4" -
3/4" 1-1/8" - 41/64" 27/64" 7/8" -
7/8" 1-5/16" - 3/4" 31/64" 63/64" -
1" 1-1/2" - 55/64" 35/64" 1-3/64" -
* This is the diameter across the flats. It is also the size of wrench to use.