#8 Screw Size and Thread Specifications
#8 is a common numbered screw size. #8-32 (32 TPI) is widely used in electronics, machinery, and hardware. Diameter is approximately 0.164 in (4.2 mm), close to metric M4.
Specifications
| Specification | Value |
|---|---|
| Designation | #8-32 (common) |
| Diameter | 0.164 in (4.2 mm) |
| Threads per inch (TPI) | 32 |
| Tap drill size | #29 |
| Closest metric equivalent | M4 |
Head types
| Screw size | Common head types |
|---|---|
| #8 | Pan head, flat head, round head (Phillips, slot, hex) |
Common uses
#8 screws are used in electronics, machinery, furniture, and general hardware. #8-32 is a standard thread for machine screws and is widely available.
Related tools
Related charts
FAQ
What is #8 screw size?
#8 is a numbered (wire gauge) screw size. #8-32 means a #8 diameter with 32 threads per inch. Diameter is approximately 0.164 in (4.2 mm).
What drill size for #8-32 tap?
Use a #29 drill for #8-32 tapping.
What metric screw is closest to #8?
M4 is the closest metric equivalent to #8. See M4 bolt size for full specs.