Hex Bolt vs Hex Cap Screw
Both have hex heads, but they are different products. A hex cap screw has a washer face under the head, a chamfered point and tighter tolerances; a hex bolt is made to be used with a nut.
Differences (ASME B18.2.1)
| Hex bolt | Hex cap screw | |
|---|---|---|
| Intended use | With a nut | In a tapped hole or with a nut |
| Washer face | No | Yes |
| Point | Plain (may be unchamfered) | Chamfered |
| Tolerances | Wider | Tighter (body, head, length) |
| Thread length | Bolt formula | Cap screw formula |
| Head height | Slightly different | Slightly different |
These tables carry the same figures as the printed sheet below.
The printed sheet
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Text version of this sheet
ASME B18.2.1 · hex bolt vs hex cap screw
What it is
FIELD IDENTIFICATION
HEX BOLT
Both have hex heads, but they are different products. A hex cap screw has a washer face under the
head, a chamfered point and tighter tolerances; a hex bolt is made to be used with a nut.
HEX CAP SCREW
washer face
Cap screw: washer face, chamfered point,
tighter tolerances
Differences (ASME B18.2.1)
Hex bolt
Hex cap screw
Intended use
With a nut
In a tapped hole or with a nut
Washer face
No
Yes
Point
Plain (may be unchamfered)
Chamfered
Tolerances
Wider
Tighter (body, head, length)
Thread length
Bolt formula
Cap screw formula
Head height
Slightly different
Slightly different
Key points
A grade mark tells you strength, not which of the two products you are holding.
Most "hex bolts" sold in industrial distribution are actually hex cap screws; order to the product standard you need.
Governing standards: ASME B18.2.1-2012 (R2021). Editions shown are the latest confirmed as of September 2026. The drawing and the governing standard always take
precedence over this sheet.
torquing any fastener. Verify the current governing standard, project documents, OEM requirements, size, thread, coating and lot certification. To the fullest extent permitted by law, The Fastener App disclaims liability
arising from reliance on this reference.
Fastener Guide reference FG-EEF331 · thefastenerapp.com/fastener-guide/technical-reference/hex-bolt-vs-hex-cap-screw · © The Fastener App. Reference only — verify the current governing standard, drawing and manufacturer data before specifying or installing.
