Drill size · tolerance callout · fixed vs. floating fastener
⚠ This tool applies to standard drilled clearance holes only. It does NOT apply to countersunk (CSK) or counterbored (CBORE) holes. Verify all callouts against applicable drawing standards (ASME Y14.5 / ISO 2768).
Select Fastener Size
Fastener Condition — Fixed or Floating?
Fixed Fastener
Fastener is threaded into one part (e.g. stud, tapped hole). Only one mating part has a clearance hole.
Floating Fastener
Fastener passes through clearance holes in all mating parts (e.g. bolt + nut, bolt through two plates).
Clearance Fit Quality
Close
Tight assembly, precise location. Less tolerance stackup.
Normal
General purpose. Most structural assemblies.
Loose
Easy assembly, thermal growth, coated parts.
Hole Tolerance Format for Drawing Callout
Symmetric ±
e.g. Ø.201 ± .005
Table Tolerance
Per drilled hole tolerance table (unequal bilateral)
Application Context — helps AI tailor recommendations