METRIC CLEARANCE HOLE CALCULATOR


Metric clearance hole calculator for bolts and screws to calculate the recommended clearance hole sizes from M1.6 through M64  in three classes of clearance using close-, normal- and loose-fit category. The recommended metric drill bit size for each class of clearance hole is shown in calculation results with nearest substitute inch drill bit size.

Metric clearance hole calculator is according to ASME B18.2.8 standard.

Metric Clearance Hole Calculator:

INPUT PARAMETERS
Nominal Screw Size
Fit Class

 


Clearance Hole
RESULTS
Parameter Value
Nominal Screw Size --- mm
Fit Class --- --
Nominal Metric Drill Size --- mm
Nearest Inch Drill Size --- in
Minimum Hole Diameter --- mm
Maximum Hole Diameter ---

Definitions:

Clearance hole: A hole on a part where threaded section of a bolt can pass.

Drill bit: A cutting tool used in drilling machines to drill a hole.

Supplements:

Reference:

  • Oberg, E. , Jones ,F.D. , Horton H.L. , Ryffel H.H., (2016) . Machinery's Handbook . 30th edition.  Industrial Press Inc.
  • Oberg, E. , Jones ,F.D. , Horton H.L. , Ryffel H.H., (2012) . Machinery's Handbook . 29th edition.  Industrial Press Inc.
  • ASME B18.2.8-1999, Clearance holes for bolts, screws and studs