Find a practical metric tap-drill size and clearance-hole size for common fastener work, with deeper controls for experienced users.
Choose a common metric thread and get the two hole sizes you need.
Recommended tap drill8.50 mm
Normal fit clearance hole11.00 mm
For 10.00 mm major diameter × 1.50 mm pitch.
Use the tap-drill result for cutting an internal thread. Use the clearance result when the bolt should pass through the first part. Confirm critical holes against the applicable standard and fastener manufacturer data.
What this tool covers
Use the tap-drill result when creating an internal thread. Use the clearance-hole result when a bolt or screw must pass through the first component.
M14 clearance row — corrected
Correction (2026-10-28): M14 now shows Close 15.0 / Normal 15.5 / Loose 16.5 mm, per the researched ISO 273 / EN 20273 table. The previous 15.0 / 15.0 / 16.0 mm values came from the original v31 build and did not match three independent reproductions of that table. ISO 273:1979 is withdrawn — cite EN 20273 for contracts, and confirm critical holes against the applicable standard.
Why fit matters
A close, normal or loose clearance fit changes the drill size. Material, tolerance, coating and the actual fastener can also affect the final choice.