What Does M10 Mean on a Screw?
Quick answer: M10 identifies an ISO metric thread with a nominal major diameter of 10 millimeters. The complete designation should also give the pitch—such as M10 × 1.5—and usually the fastener length.
Key points
- M means metric thread.
- 10 is the nominal outside diameter in millimeters.
- M10 coarse pitch is commonly 1.5 mm, but fine pitches also exist, so never assume when fit matters.
- Length, strength class, head and material are specified separately.
How to choose or use it
Match both diameter and pitch to the nut or tapped hole. Check markings and technical data for strength class, and use calipers plus a metric thread gauge when identifying unknown hardware.
Browse the relevant IMSCREWS product collection after confirming the required dimensions and specification.
Installation and safety checklist
- Confirm the receiving material, hole preparation and mating thread.
- Verify diameter, pitch, length, head, drive, material and finish.
- Use a well-fitting tool, keep it aligned and tighten only to the required seating or specified torque.
- For structural, overhead or safety-critical joints, follow the approved design, code and manufacturer data.