Allen Wrench Size Chart

Allen wrench size chart explained below consists of the hex size, suitable long arm length and also short arm length. It is designed to help you in the workshop and use a proper Allen wrench when needed. Keep in mind that wrenches made from stainless steel won’t corrode or rust regardless of how and where they are used. This material is immune to rusk completely. This is important due to the fact the wrench will always maintain its size.

The tables below are basically identical but available in different measurements. The first one is millimeters or metric while the second is in inches, imperial size chart. The third table is related to more specific Allen keys and it shows the correlation between the hex size in inches and the long/short arm ibn millimeters. The first two charts refer to stainless steel models. The third is based for different materials and for models with the round head (used to make insertion much easier). See also digital torque wrench review.