General Tolerance Iso 2768-mk _verified_ Jun 2026
The Ultimate Guide to ISO 2768-mK: Streamlining Your Manufacturing Drawings
While there are other classes—such as "f" (fine) for high precision or "c" (coarse) for loose fits—the combination is the most widely used, representing about 80% of typical manufacturing requirements.
30 to 120 mm: ±0.8 mm
ISO 2768 is an international standard created by the International Organization for Standardization. It provides a set of general tolerances for linear and angular dimensions without individual tolerance indications. general tolerance iso 2768-mk
Defines the tolerance class for linear and angular dimensions (Medium).
Choosing the correct tolerance class is a critical design decision that directly impacts manufacturing cost and feasibility.
Choosing the right class is a balancing act. While an "m" classification often provides a safe, cost-effective default, critical features still demand their own specific tolerances. By mastering the rules and tables outlined in this guide, you can harness the full potential of the ISO 2768 standard to streamline your designs, control manufacturing costs, and ensure consistent quality on every part you produce. The Ultimate Guide to ISO 2768-mK: Streamlining Your
It keeps drawings clean. Only critical dimensions (like a bearing fit or a sealing surface) need specific ± tolerances.
ISO 2768-mk is the "Goldilocks" of manufacturing tolerances—not too tight, not too loose. It ensures that parts are functional and interchangeable without unnecessary manufacturing expenses. When you see it on a drawing, you’re looking at a standard of and Medium Geometrical control .
When a technical drawing specifies in its title block, it means the manufacturer must adhere to "medium" (m) tolerances for linear/angular dimensions and "tolerance class K" (K) for geometrical features like flatness, straightness, and symmetry. 1. Deconstructing the Code: What Does "mK" Mean? Defines the tolerance class for linear and angular
While ISO 2768-mK is incredibly versatile, it is not a silver bullet. You should bypass general tolerances in the following scenarios:
For external radii and chamfers, the standard applies a tighter set of rules to ensure parts are safely deburred without altering structural integrity: Nominal Size Range (mm) Tolerance Class (Medium) 0.5 to 3 Over 3 to 6 Over 6 Permissible Deviations for Angular Dimensions
For linear measurements like external/internal sizes, heights, and distances. Nominal Range (mm) Tolerance (± mm) 120 to 400 400 to 1000 Geometric Tolerances (Class K)
ISO 2768-mK standard defines general tolerances for dimensions and geometric features on technical drawings where specific tolerances are not indicated. It simplifies drawings by providing a default "medium" level of precision, ensuring parts fit together without over-specifying every dimension. Meaning of "mK" "m" (Medium) : Refers to ISO 2768-1 , covering general tolerances for linear and angular dimensions (lengths, diameters, radii, chamfers). "K" (Medium) : Refers to ISO 2768-2 , covering general geometrical tolerances
The letters 'm' and 'k' are not arbitrary; they denote specific tolerance classes.
The Ultimate Guide to ISO 2768-mK: Streamlining Your Manufacturing Drawings
While there are other classes—such as "f" (fine) for high precision or "c" (coarse) for loose fits—the combination is the most widely used, representing about 80% of typical manufacturing requirements.
30 to 120 mm: ±0.8 mm
ISO 2768 is an international standard created by the International Organization for Standardization. It provides a set of general tolerances for linear and angular dimensions without individual tolerance indications.
Defines the tolerance class for linear and angular dimensions (Medium).
Choosing the correct tolerance class is a critical design decision that directly impacts manufacturing cost and feasibility.
Choosing the right class is a balancing act. While an "m" classification often provides a safe, cost-effective default, critical features still demand their own specific tolerances. By mastering the rules and tables outlined in this guide, you can harness the full potential of the ISO 2768 standard to streamline your designs, control manufacturing costs, and ensure consistent quality on every part you produce.
It keeps drawings clean. Only critical dimensions (like a bearing fit or a sealing surface) need specific ± tolerances.
ISO 2768-mk is the "Goldilocks" of manufacturing tolerances—not too tight, not too loose. It ensures that parts are functional and interchangeable without unnecessary manufacturing expenses. When you see it on a drawing, you’re looking at a standard of and Medium Geometrical control .
When a technical drawing specifies in its title block, it means the manufacturer must adhere to "medium" (m) tolerances for linear/angular dimensions and "tolerance class K" (K) for geometrical features like flatness, straightness, and symmetry. 1. Deconstructing the Code: What Does "mK" Mean?
While ISO 2768-mK is incredibly versatile, it is not a silver bullet. You should bypass general tolerances in the following scenarios:
For external radii and chamfers, the standard applies a tighter set of rules to ensure parts are safely deburred without altering structural integrity: Nominal Size Range (mm) Tolerance Class (Medium) 0.5 to 3 Over 3 to 6 Over 6 Permissible Deviations for Angular Dimensions
For linear measurements like external/internal sizes, heights, and distances. Nominal Range (mm) Tolerance (± mm) 120 to 400 400 to 1000 Geometric Tolerances (Class K)
ISO 2768-mK standard defines general tolerances for dimensions and geometric features on technical drawings where specific tolerances are not indicated. It simplifies drawings by providing a default "medium" level of precision, ensuring parts fit together without over-specifying every dimension. Meaning of "mK" "m" (Medium) : Refers to ISO 2768-1 , covering general tolerances for linear and angular dimensions (lengths, diameters, radii, chamfers). "K" (Medium) : Refers to ISO 2768-2 , covering general geometrical tolerances
The letters 'm' and 'k' are not arbitrary; they denote specific tolerance classes.