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.

INPUT PARAMETERS
Nominal Screw Size	M1.6 M2 M2.5 M3 M4 M5 M6 M8 M10 M12 M14 M16 M20 M24 M30 M36 M42 M48 M56 M64
Fit Class	Normal Close Loose

Please Wait... 

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.

Supplements:

• Thread Calculators and Charts
• Metric clearance hole chart

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