Clevis Pin Sizes Chart according to ASME B18.8.1 standard.

- Material and heat treatment: Clevis pins shall be made from low carbon steel unless otherwise specified. Case hardened pins shall have a case depth of 0.010 to 0.016 in.

- The axis of hole through shank shall not be offset from the axis of pin by more than 0.010 in. for the 3/16 and 1/4 in. nominal pin size and 0.020 in. for all larger pin sizes.

- The tabulated length apply to pin intended for use with standard clevises, without spacers.

- Designation: Name, Nominal Size, Length, Material and Finish. Ex: Pin, Clevis, 1/4 x 0.77, Steel, Zinc Plated

Nominal Pin Size


Clevis Pin Sizes
Parameter Value
Nominal Size --- inch
Basic Pin Diameter ---
Maximum Shank Diameter [Amax] ---
Minimum Shank Diameter [Amin] ---
Maximum Head Diameter [Bmax] ---
Minimum Head Diameter [Bmin] ---
Maximum Head Height [Cmax] ---
Minimum Head Height [Cmin] ---
Head Chamfer (+/- 0.01) [D] ---
Maximum Hole Diameter [Emax] ---
Minimum Hole Diameter [Emin] ---
Maximum Point Diameter [Fmax] ---
Minimum Point Diameter [Fmin] ---
Basic Pin Length [G] 1 ---
Head to Center of Hole (Max) [Hmax] ---
Head to Center of Hole (Min) [Hmin] ---
End to Center Ref (Basic) [J] 2 ---
Head to Edge of Hole Ref (Min) [Mmin] 3 ---
Recommended Cotter Pin Nominal Size ---

Note 1: Pin Length tabulated is intended for use with standard clevis, without spacers. When other lengths are required, it is recommended that they be limited wherever possible to nominal lengths in 0.06-inch increments.

Note 2: Basic J dimension is specified for calculating hole location from underside of head on pins of lengths for non standard length clevis pins.

Note 3: For M, reference dimension provided for convenience in design layout and is not subject to inspection.

All dimensions are in inches


Cotter Pin: A pin that is fitted through a hole and then bent backwards to lock the pin in place. Cotter pins are used to lock clevis pins.



  • ASME B18.8.1-1994, Clevis Pins and Cotter Pins (Inch Series)
  • Oberg.E , Jones.D.J., Holbrook L.H, Ryffel H.H., (2012) . Machinery's Handbook. 29th edition.  Industrial Press Inc. , pp 1747
  • Oberg, E. , Jones ,F.D. , Horton H.L. , Ryffel H.H., (2016) . Machinery's Handbook . 30th edition.  Industrial Press Inc. , pp 1796