Are M8 and 5/16 the Same

Well, quick answer is no. They are not the same and they are not interchangeable, although they can work under certain circumstances. The most important part is understanding the meaning of M8 and 5/16 to refer to the size of a metric screw or bolt, so then we can see why they aren’t the same thing!

Will a 5/16 socket fit a 8mm nut?

5/16 is technically a little smaller then 8mm but if it fits over it then it’s a better option. If it’s not coming off that’s another issue.

What size is an M8 bolt in inches?

MetricClosest InchM8-1.255/16-18 (Smaller)M10-1.53/8-16 (Smaller)M12-1.751/2-13 (Larger)M14-2.09/16-12 (Larger)