The Complete Guide to the ISO 2768-mH Tolerance Chart In the world of mechanical design and manufacturing, precision is paramount. However, explicitly defining a specific tolerance for every single feature on a technical drawing can be incredibly tedious and time-consuming. To streamline the drafting process, international engineering standards exist to establish "general tolerances." One of the most widely used standards for this purpose is .
| Nominal Size Range (mm) | Tolerance Class | | :--- | :--- | | | m (Medium) | | 0.5 up to 3 | ±0.1 | | over 3 up to 6 | ±0.1 | | over 6 up to 30 | ±0.2 | | over 30 up to 120 | ±0.3 | | over 120 up to 400 | ±0.5 | | over 400 up to 1000 | ±0.8 | | over 1000 up to 2000 | ±1.2 | | over 2000 up to 4000 | ±2 |
What is ISO 2768? | CNC Machining Tolerance Standards - Fictiv iso 2768-mh tolerance chart
Because it pairs medium linear limits with fine geometric rules ("h"), it ensures that components fit together cleanly without excessive warping, twist, or misalignment.
Disclaimer: As of 2026, the 1989 version of ISO 2768 remains the active standard. The Complete Guide to the ISO 2768-mH Tolerance
For Class H, the total permissible circular run-out (radial and axial) is strictly limited to a maximum of . Why Use ISO 2768-mh in Manufacturing?
In the world of engineering and manufacturing, tolerances play a crucial role in ensuring that parts and assemblies fit together properly. One of the most widely used tolerance standards is ISO 2768, which provides a set of general tolerances for linear and angular dimensions. In this blog post, we'll take a closer look at the ISO 2768-MH tolerance chart and its applications. | Nominal Size Range (mm) | Tolerance Class
Note: This applies to external radii and chamfer heights (not edge radii). Dimension Length (mm) Tolerance m (Medium) (mm) Above 0.5 up to 3 Above 3 up to 6 Above 6 up to 30 Above 30 up to 120 Table C: Angular Dimensions (ISO 2768-1)