Enter your values
About this calculation
Choose a practical clearance hole for a metric bolt. This page gives the formula, a direct calculator and practical context so the result can be checked rather than treated as a black box.
Common mistakes
Mixing units, using nominal rather than measured dimensions, omitting efficiency or friction factors, and applying theoretical results without an appropriate safety factor are the most common errors.
Useful equipment
Find a metric drill bit set on Amazon US.
View equipment on Amazon