What size wrench or spanner fits #8-32?

#8-32 bolt uses a 11/32 wrench or spanner, measured across the flats of the hex head.

What is the torque for #8-32?

A typical tightening torque for #8-32 bolt in Grade 2 on dry threads is about 3.5 Nm (2.58 ft·lb). Always confirm against the manufacturer spec for important joints.

What thread pitch and tap drill does #8-32 use?

#8-32 bolt has a thread pitch of 32 TPI (threads per inch) and uses a #29 (3.5 mm) tap drill, with a 9/32 clearance hole.

What is #8-32 used for?

#8-32 is commonly used in electronics, small instruments. It is one of the most popular sizes in its category.

What is the closest metric size to #8-32?

The closest metric size to #8-32 is approximately ~M4, though they are not exactly interchangeable.

Home › Imperial / SAE Bolts › #8-32

#8-32 bolt size

11/32 wrench

across-flats spanner / socket size for #8-32

#8-32 bolt — Electronics, small instruments.

Full specification

System	Imperial UNC
Nominal diameter	#8-32 (0.164 in / 4.17 mm)
Thread pitch	32 TPI
Wrench / spanner (across flats)	11/32
Tap drill	#29 (3.5 mm)
Clearance hole	9/32
Common grade / class	Grade 2
Typical torque	3.5 Nm (2.58 ft·lb)
Closest other-system size	~M4

🔧 Torque unit converter

Newton-metres (Nm) Foot-pounds (ft·lb) Inch-pounds (in·lb)

Pre-filled with the typical torque for #8-32 (Grade 2, dry). Edit any field to convert.

⚠️ Torque values here are general references for Grade 2 on clean, dry threads. Lubrication, coatings, and the joint material change the figure significantly. For structural, automotive, or safety-critical work, always use the torque specified by the manufacturer or engineer.

About #8-32

Electronics, small instruments.

A #29 drill is the standard tap drill for #8-32-32 UNC thread. The standard clearance hole is 9/32.

#8-32 is part of the Unified National Coarse (UNC) thread series, defined in ASME B1.1. The wrench size 11/32 is measured across the flats of the hex head.

Common applications

#8-32 bolts are widely used in:

Electronics, small instruments
General machinery and equipment assembly
Automotive components and repairs
Structural connections (when specified by engineer)
Industrial maintenance and repair

Material and grade information

The typical grade for #8-32 is Grade 2. This indicates:

Grade 2: Low carbon steel
Tensile strength: 50,000 PSI
Yield strength: 30,000 PSI
Common coatings: Zinc plated, hot-dip galvanized, or plain

Frequently asked questions

What size wrench or spanner fits #8-32?: #8-32 bolt uses a 11/32 wrench or spanner, measured across the flats of the hex head.
What is the torque for #8-32?: A typical tightening torque for #8-32 bolt in Grade 2 on dry threads is about 3.5 Nm (2.58 ft·lb). Always confirm against the manufacturer spec for important joints.
What thread pitch and tap drill does #8-32 use?: #8-32 bolt has a thread pitch of 32 TPI (threads per inch) and uses a #29 (3.5 mm) tap drill, with a 9/32 clearance hole.
What is #8-32 used for?: #8-32 is commonly used in electronics, small instruments. It is one of the most popular sizes in its category.
What is the closest metric size to #8-32?: The closest metric size to #8-32 is approximately ~M4, though they are not exactly interchangeable.