Iso 2768-mh Tolerance Chart Updated Jun 2026

Class (Medium) is the most common tolerance class for CNC machined metal parts. Below are the permissible deviations for linear measures and angles. Nominal Size Range (mm) Linear Dimensions (mm) Ext. Radii & Chamfers (mm) Angular Dimensions ±plus or minus ±plus or minus ±plus or minus ∘raised to the composed with power (up to 10mm) ±plus or minus ±plus or minus ±plus or minus ∘raised to the composed with power 30' (10-50mm) ±plus or minus ±plus or minus ±plus or minus ∘raised to the composed with power 20' (50-120mm) > 30 to 120 ±plus or minus ±plus or minus ±plus or minus ∘raised to the composed with power 10' (120-400mm) > 120 to 400 ±plus or minus ±plus or minus ±plus or minus ∘raised to the composed with power 5' (over 400mm) > 400 to 1000 ±plus or minus Sources: Part 2: Geometrical Tolerances (Class "H")

Note: Some drawings use “mK” for shafts. mH is specifically for holes/internal features. iso 2768-mh tolerance chart