Fit Tool

Metric Fits Calculator

Calculate ISO metric hole and shaft limits from nominal diameter, fit designation, and tolerance grade. Includes common hole-basis fits, preferred shaft-basis fits, and manual ISO letter selection.

Inputs

Outputs

Parameter Value

Tolerance Zones

Below basic size Basic size Above basic size
Hole
Shaft

References

Based on ISO system of limits and fits tolerance-unit equations and fundamental-deviation relationships as tabulated in Machinery's Handbook, 29th Edition, Industrial Press, page 653 and adjacent ISO metric limits and fits tables. Values are calculated in micrometers and converted to millimeters for displayed limits.

Use this as a design calculator and verify production-critical fits against the governing ISO 286 table, drawing standard, and supplier process capability.