Defines TG1 (highest precision) to TG7 (lowest precision), with TG6 being common for typical thermoplastic applications.
Match your nominal part dimensions to the correct row and column in the ISO 20457 table.
Overall part performance, fits, clearances, and functional interactions between separate molded pieces. 2. Series W (Tool-Dependent Tolerances)
Purchase the full ISO 20457:2018 from the International Organization for Standardization . iso 20457 tolerance table pdf
To properly reference this standard on your engineering prints or PDF drawings, you should include a specific note in the title block. Recommended Drawing Callout Format:
These tolerances apply directly to the dimensions determined by the physical mold cavity. Series W is further split into two sub-categories: Tool-Dependent Dimensions ( WAcap W sub cap A
Adding glass fibers decreases overall shrinkage but introduces directional variations (parallel vs. perpendicular to the melt flow direction), which can induce warpage. Defines TG1 (highest precision) to TG7 (lowest precision),
ISO 20457 categorizes tolerances into two distinct application groups based on whether the dimensions are tool-dependent or affected by post-molding assembly processes: 1. Series NW (Non-Tool-Dependent / Assembly Tolerances)
: These range from high precision (TG1) to normal production (TG9). For standard thermoplastics in injection molding, is a frequently used baseline for general tolerances. Dimensional Categories
What or resin blend are you using?
Practical application guidance
ISO 20457 is the internationally recognized standard for tolerances and acceptance conditions of plastic molded parts. This comprehensive guide explains everything you need to know about the ISO 20457 tolerance table, how to interpret tolerance grades, and where to obtain the official PDF documentation.
Engineers and quality control managers frequently search for the ISO 20457 PDF to access its standardized data tables. These tables eliminate guesswork by providing: how to interpret tolerance grades
| Nominal Outside Diameter ($d_n$) (mm) | Tolerance (mm) | | :--- | :--- | | $d_n \le 16$ | +0.3 / 0 | | $16 < d_n \le 63$ | +0.4 / 0 | | $63 < d_n \le 110$ | +0.5 / 0 | | $110 < d_n \le 160$ | +0.6 / 0 | | $160 < d_n \le 225$ | +0.7 / 0 | | ... | ... |