| Range of Nominal Length (mm) | Straightness / Flatness | Perpendicularity | Symmetry / Runout | | :--- | :--- | :--- | :--- | | Up to 100 | 0.1 mm | 0.2 mm | 0.2 mm | | >100 to 300 | 0.2 mm | 0.3 mm | 0.3 mm | | >300 to 1000 | 0.3 mm | 0.4 mm | 0.4 mm | | >1000 to 3000 | 0.4 mm | 0.5 mm | 0.5 mm | You will often see a block in the title bar of a drawing stating: General Tolerances ISO 2768-mK .
| Nominal Size Range (mm) | 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 | Iso 2768 General Tolerances Pdf
| Class | Description | Accuracy | Cost Implication | | :--- | :--- | :--- | :--- | | | Fine | High precision | Higher cost | | m | Medium | Standard workshop accuracy | Most common / Balanced | | c | Coarse | Loose tolerance | Lower cost | | v | Very coarse | Very loose | Lowest cost | | Range of Nominal Length (mm) | Straightness
If you have searched for an you are likely looking for a clear, authoritative guide or a downloadable reference table. This article serves as that resource. We will break down what ISO 2768 is, its two parts (Part 1 for linear/angular and Part 2 for geometrical), the tolerance classes, and how to apply them. What is ISO 2768? ISO 2768 is an international standard created by the International Organization for Standardization (ISO). It is officially titled: "General tolerances — Part 1: Tolerances for linear and angular dimensions without individual tolerance indications" and "Part 2: Geometrical tolerances for features without individual tolerance indications." We will break down what ISO 2768 is,