Tolerances in mm for nominal size ranges (up to 3000mm).
| Nominal Size Range | f (Fine) | m (Medium) | c (Coarse) | v (Very Coarse) | | :--- | :--- | :--- | :--- | :--- | | 0.5 up to 3 | ±0.05 | ±0.1 | ±0.2 | — | | >3 up to 6 | ±0.05 | ±0.1 | ±0.3 | ±0.5 | | >6 up to 30 | ±0.1 | ±0.2 | ±0.5 | ±1.0 | | >30 up to 120 | ±0.15 | ±0.3 | ±0.8 | ±1.5 | | >120 up to 400 | ±0.2 | ±0.5 | ±1.2 | ±2.5 | | >400 up to 1000 | ±0.3 | ±0.8 | ±2.0 | ±4.0 | | >1000 up to 2000 | ±0.5 | ±1.2 | ±3.0 | ±6.0 | | >2000 up to 3000 | — | ±2.0 | ±4.0 | ±8.0 |
Expert Tip: For a 100mm shaft (Class "m"), the tolerance is ±0.3mm. If you need tighter than this, you must specify the dimension individually (e.g., 100 +0.02/-0.00).
The "Exclusive" part most PDFs lack is the geometrical section. If you write ISO 2768-m without a -2, you only get linear tolerances. To get geometry, you need to specify the tolerance class for form and position. iso 2768 general tolerances pdf exclusive
The Notation: ISO 2768-mH (Linear class "m", Geometrical class "H")
Add this to your title block or general notes section of your engineering drawing.
GENERAL TOLERANCES PER ISO 2768-1 & 2 (CLASS mK) Tolerances in mm for nominal size ranges (up to 3000mm)
Linear Dimensions (ISO 2768-1 Class m):
Angular Dimensions (ISO 2768-1): ±30' for lengths up to 50mm.
Geometrical Tolerances (ISO 2768-2 Class K): GENERAL TOLERANCES PER ISO 2768-1 & 2 (CLASS
BREAK EDGES: Maximum 0.2mm x 45° unless otherwise specified. REMOVE ALL BURRS prior to inspection.
This is where most engineers fail. Even if your linear dimensions are "Fine," your flatness or perpendicularity might be "Coarse."
ISO 2768-2 applies to four main characteristics: Straightness, Flatness, Perpendicularity, Symmetry, and Runout.
ISO 2768 groups tolerances by:
(Exact numeric tables are normative content of the ISO standard; consult the standard or licensed reproductions for precise values.)