Hex head screws are commonly used fasteners in construction, machinery, and mechanical assemblies. They feature a hexagonal head that allows tightening with a wrench or socket, making them suitable for applications requiring strong and secure fastening.
Understanding a hex head screw size chart helps identify the correct screw diameter, head size, and tool compatibility.
Standard Hex Head Screw Size Chart (Inches)
| Screw Diameter | Head Width (Across Flats) | Head Height | Common Wrench Size |
|---|---|---|---|
| #10 | 3/8 in | 0.150 in | 3/8 in |
| 1/4 in | 7/16 in | 5/32 in | 7/16 in |
| 5/16 in | 1/2 in | 13/64 in | 1/2 in |
| 3/8 in | 9/16 in | 1/4 in | 9/16 in |
| 7/16 in | 5/8 in | 19/64 in | 5/8 in |
| 1/2 in | 3/4 in | 5/16 in | 3/4 in |
| 9/16 in | 13/16 in | 23/64 in | 13/16 in |
| 5/8 in | 15/16 in | 25/64 in | 15/16 in |
These sizes follow common ANSI/ASME standards used in many mechanical and construction applications.
Metric Hex Head Screw Size Chart
Metric hex head screws follow ISO standards and use millimeter measurements.
| Screw Size | Head Width (mm) | Head Height (mm) | Wrench Size |
|---|---|---|---|
| M5 | 8 mm | 3.5 mm | 8 mm |
| M6 | 10 mm | 4 mm | 10 mm |
| M8 | 13 mm | 5.3 mm | 13 mm |
| M10 | 17 mm | 6.4 mm | 17 mm |
| M12 | 19 mm | 7.5 mm | 19 mm |
| M14 | 22 mm | 8.8 mm | 22 mm |
| M16 | 24 mm | 10 mm | 24 mm |
Metric hex head screws are widely used in automotive, machinery, and international manufacturing.
Hex Head Screw Measurements Explained
Several measurements define hex head screw dimensions.
Thread Diameter
The thickness of the screw’s threaded shaft.
Head Width (Across Flats)
The distance between two opposite sides of the hex head. This determines the wrench or socket size.
Head Height
The thickness of the hex head from top to bottom.
These measurements ensure screws fit properly in mechanical assemblies.
Common Uses of Hex Head Screws
Hex head screws are commonly used in:
- Metal and wood construction
- Automotive components
- Machinery assembly
- Structural frameworks
- Industrial equipment
Their hexagonal head design provides a strong grip and torque during installation.
FAQs (Frequently Asked Questions)
What is a hex head screw?
A hex head screw is a fastener with a six-sided head that can be tightened using a wrench or socket.
How do you measure hex head screw size?
Measure the thread diameter, head width across flats, and screw length.
What wrench size fits a 1/2 inch hex head screw?
A 3/4 inch wrench or socket typically fits a 1/2 inch hex head screw.
Are hex head screws and hex bolts the same?
They are similar, but hex bolts usually require a nut, while hex head screws may thread directly into materials.
Final Thoughts
A hex head screw size chart helps identify the correct screw dimensions and compatible tools for installation. These fasteners follow standardized measurements to ensure consistent performance across construction, mechanical, and industrial applications.
Selecting the proper hex head screw size improves fastening strength, installation efficiency, and overall structural reliability.