Counterbore Hole Dimensions for Metric Socket Head Cap Screws Calculator is working in line with the charts given in the
Machinery's Handbook, 30th page 1662.
Metric Counterbore Chart and Calculator:
Note ^{1}: Close Fit: The close fit is normally limited to holes for those lengths of screws which are threaded
to the head in assemblies where only one screw is to be used or where two or more screws are to be used
and the mating holes are to be produced either at assembly or by matched and coordinated tooling.
Note ^{2}: Normal Fit: The normal fit is intended for screws of
relatively long length or for assemblies involving two or more screws where the
mating holes are to be produced by conventional tolerancing methods.

RESULTS 
Parameter 
Value 
Nominal Screw Size 


 
Max. Body Diameter [D_{max}] 


mm 
Fit Class 


 
Nominal Metric Drill Size [A] 


mm 
Counterbore Diameter [X] 


mm 
Countersink Diameter [Y] ^{1} 


Max. Head Height [H_{max}] 


Max. Transition Diameter [B_{max}] 

