M11 Bolt Size and Thread Specifications

Q: What is the standard pitch for an M11 bolt?

The standard coarse pitch for M11 is 1.5 mm. Fine pitch is often 1.25 mm where specified.

Q: What imperial fastener is closest to M11?

7/16-14 (approx.) is a practical imperial reference for M11; always verify against your application.

What is an M11 bolt?

An M11 bolt has 11 mm nominal diameter; coarse pitch is typically 1.5 mm. Availability is weaker than M10 or M12, so confirm parts before field use.

M11 is less common than M10 or M12. Check fastener catalogs for nuts, washers, and tools before relying on M11 in new designs. Spanish reference: perno M11.

Specifications

Specification	Value
Nominal diameter	11 mm
Standard pitch (coarse)	1.5 mm
Fine pitch	1.25 mm
Tap drill size	9.5 mm
Closest imperial equivalent	7/16-14 (approx.)

Hex head size

Bolt size	Hex head size
M11	18 mm

Common uses

Special machinery, some automotive and industrial spares that specify M11.

Related tools

Metric to Imperial Screw Converter — compare M11 to common inch threads.
Tap Drill Calculator — tap drill size for M11 and other metric threads.
Thread Identifier Tool — match measured diameter and pitch to a standard.

Related charts

Universal Screw & Bolt Size Chart — metric, imperial, pitch, and tap drill in one view.
Tap Drill Chart — metric tap drill sizes.

FAQ

What is the standard pitch for an M11 bolt?

The common coarse pitch for M11 is 1.5 mm. Fine pitch is often 1.25 mm where specified.

What drill size should be used for tapping M11 threads?

For M11 x 1.5 coarse thread, use approximately a 9.5 mm tap drill. Use our Tap Drill Calculator for other pitches.

What imperial fastener is closest to M11?

7/16-14 (approx.) is a practical reference for comparing M11 to inch hardware; verify fit for your application.

Related guide

Metric vs Imperial Fasteners