Engineering

Hole & Shaft Fit Calculator

Enter the four limits from the drawing and find out whether the parts assemble by hand, need a press, or lock - and which side of the tolerance to tighten.

The hole

Nominal size (mm)A label for the feature, not a size the part has to be.Hole minimum (mm)Hole maximum (mm)

The shaft

Shaft minimum (mm)Shaft maximum (mm)

Result

Clearance fit - assembles by hand

Clearance runs from 0.0070 mm to 0.0410 mm.

Loosest assembly (hole max − shaft min)0.0410 mm

Tightest assembly (hole min − shaft max)0.0070 mm

Hole band21.0 µm

Shaft band13.0 µm

Combined band34.0 µm

Max interferencenone

What this fit implies

Every combination assembles by hand: the tightest pair still has 0.0070 mm of clearance. That is a running or locating fit - the parts move relative to each other unless something else clamps them.
Of the 0.0340 mm of total tolerance, 62% is in the hole. Tightening whichever side carries the larger share is usually the cheaper way to move the fit.

Arithmetic on the four limits you enter. It does not choose a fit for you and it does not name an ISO fit class - that needs the tolerance tables, and a fit class quoted from memory is how bores get scrapped.

What you provide

Nominal size
Hole minimum and maximum
Shaft minimum and maximum