If a single feature on a part requires a hyper-precise fit (like a bearing bore), manually override the general standard by writing a specific tolerance next to that exact dimension on the drawing.
A major update is underway. The new standard, (which includes both parts), is currently at the Final Draft International Standard (FDIS) stage and was published in late 2025. This revision brings the GPS (Geometrical Product Specifications) framework up to date, expanding tolerance ranges and clarifying specifications for modern applications. This guide covers the current industry norms while noting key features of the upcoming revision.
ISO 2768-2 simplifies the drawing by defining tolerance zones for features lacking specific geometrical callouts. It categorizes tolerances into three classes: (fine) K (medium) L (coarse)
Ranges from ±0.1 mm (up to 10 mm length) to ±2.0 mm (up to 3000 mm length). Perpendicularity iso 2768 general tolerances pdf exclusive
Tolerances are selected based on the length of the largest surface or line.
Therefore, while the content of the standard describes universal engineering limits, the document itself remains an exclusive asset, creating a friction point between the need for widespread standardization and the revenue model of the ISO.
Below is the exclusive breakdown of permissible deviations in mm. Note how tolerance increases with nominal size. If a single feature on a part requires
For example, a note reading informs the manufacturer that all linear dimensions without individual tolerances must adhere to the Medium (m) tolerance class from Part 1. Additionally, all geometric features (like flatness) must adhere to the K class from Part 2.
This part controls geometric features such as form and position that lack individual indications. 8880138.s21i.faiusr.com ISO 2768-2
"In this case, Ø47.8mm and Ø52.5mm would be outside the acceptable range, and you would be within your rights to ask the supplier to remake them." It categorizes tolerances into three classes: (fine) K
ISO 2768-1 applies to dimensions that are produced by metal removal (e.g., CNC machining) or are formed from sheet metal. It provides four distinct tolerance classes, allowing you to select the level of precision that best matches your part's function and your manufacturing capabilities.
What are you using? (e.g., CNC milling, sheet metal, injection molding) What material is the part made of?
The standard provides a set of tolerance classes, each with its own set of tolerance values, which can be used to specify the acceptable limits of variation for a particular feature.