Clearance Hole Calculator For Bolts and Screws

Clearance hole calculator to find the recommended clearance hole sizes from #0 through 1.5 in for inch bolts, screws and studs in three classes of clearance using close-, normal- and loose-fit category. The recommended inch drill bit size for each class of clearance hole is shown in calculation results. The calculator also shows nearest substitute metric drill bit size for inch fasteners.

Clearance hole calculator is according to ASME B18.2.8  - " Clearance holes for bolts, screws and studs" standard.

Clearance Hole Calculator:

INPUT PARAMETERS
Nominal Screw Size	#0 #1 #2 #3 #4 #5 #6 #8 #10 1/4 5/16 3/8 7/16 1/2 5/8 3/4 7/8 1 1 1/8 1 1/4 1 3/8 1 1/2
Fit Class	Normal Close Loose

Please Wait... 

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

• Thread Calculators and Charts
• 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