Drill Size for Cutting Tap Calculator (mm)
MThD  mm Pitch Coarse DSize mm
MThD  mm Pitch  Fine DSize mm
Drill Size for Forming Tap Calculator (mm)
MThD  mm Pitch Coarse DSize mm
MThD  mm Pitch  Fine DSize mm

MThD - Major Thread Diameter mm;   Pitch - mm;  DSize - drill size mm