Specifications for Depth of Fastener Threads

View American or Metric standard from the tables below and see your thread depths for different materials.

American - Specifications for Depth of Threads

Thread Tapped Through (Inches) (SS) (Alum., Brass, Steel, Nylon) Blind Tap Depth (Inches) (Alum., Brass, SS, Steel, Nylon)
0-80 1/4 3/8 3/16
1-72 1/4 3/8 3/16
2-56 5/8 3/4 3/16
3-48 5/8 3/4 3/16
3-56 5/8 3/4 3/16
4-40 3/4 1″ 1/4
4-48 3/4 1″ 1/4
5-40 3/4 1″ 5/16
6-32 1″ 1″ 3/8
6-40 1″ 1″ 3/8
8-32 1″ 1″ 7/16
10-24 1″ 1-1/8 1/2
10-32 1″ 1-1/8 1/2
12-24 1″ 1-1/8 1/2
1/4-20 1-1/4 1-1/4 5/8
1/4-28 1-1/4 1-1/4 5/8
5/16-18 1-1/4 1-1/4 5/8
5/16-24 1-1/4 1-1/4 5/8
3/8-16 1-1/4 1-1/4 5/8
3/8-24 1-1/4 1-1/4 5/8
7/16-14 1-1/4 1-1/4 5/8
7/16-20 1-1/4 1-1/4 5/8
1/2-13 1-1/4 1-1/4 5/8
1/2-20 1-1/4 1-1/4 5/8

Metric - Specifications for Depth of Threads

Thread Code Tapped Through (mm) (SS) (Alum., Brass, Steel, Nylon) Blind Tap Depth (mm) (Alum., Brass, S.S., Steel, Nylon)
M2X0.4 2004 6 9 4.7
M2.5X0.45 2545 16 19 4.7
M3X0.5 3005 19 25 6.3
M3.5X0.6 3506 25 25 9.5
M4X0.7 4007 25 25 11.1
M5X0.8 5008 25 28 12.7
M6X1 6010 31 31 16
M8X1.25 8025 31 31 16

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