Materials, geometry and pressure
ISO 2768: General tolerances
What applies when a dimension on the drawing has no tolerance of its own.
Reference noteThis page is an independent plain-language summary written by QUALITAS TR. It does not reproduce the standard. Always work from the current official edition, available from ISO, the International Organization for Standardization, and national standards bodies such as TSE in Turkey (official page). QUALITAS TR supports organisations against this standard; it does not certify them.
01Purpose
ISO 2768-1 specifies general tolerances for linear and angular dimensions without individual tolerance indications in four classes: fine (f), medium (m), coarse (c) and very coarse (v).
02Scope
ISO 2768-2 covered general geometrical tolerances (classes H, K, L). At ISO level it has been superseded by ISO 22081 for general geometrical specifications, but it remains widely referenced on existing drawings.
03Main requirements
- Tolerance class indicated in or near the title block, for example ISO 2768-mK
- Permissible deviations depending on nominal size range
- Separate values for broken edges and angular dimensions
- Application only where no individual tolerance is given
04Typical applications and industries
Machined and fabricated parts drawn to ISO conventions.
05Audit and inspection considerations
- Is the general tolerance class stated?
- Are inspectors applying the correct size range?
06Common nonconformities
- General tolerance not stated on drawing
- Wrong class applied by supplier
- Geometrical general tolerances ignored
07How QUALITAS TR can support
Use our tolerance calculator to evaluate limits.