Standards & Documentation
Technical specifications, reference standards, and data sources used in the FastenersStandards Pro calculator.
About Data Accuracy
Our algorithms utilize a hybrid approach of **exact table lookups** and **standardized formulas**:
- Standard Series: For standard major diameters (multipoles of standard pitches), values are retrieved directly from the digitized data tables of the respective standards (ISO 261 / ASME B1.1).
- Calculated Values: Tolerance limits, fundamental deviations, and limiting dimensions are computed using the formulas prescribed in ISO 965-1 (Section 5) and ASME B1.1 (Section 8).
ISO Standards
ISO 68-1:1998
Second Edition • 1998
ISO general purpose screw threads — Basic profile — Part 1: Metric screw threads.
ISO 261:1998
Second Edition • 1998
ISO general purpose metric screw threads — General plan.
ISO 965-1:2013
Fourth Edition • 2013
ISO general purpose metric screw threads — Tolerances — Part 1: Principles and basic data.
Legal Disclaimer
The data and calculations provided by this application are for informational and educational purposes only. While every effort has been made to ensure accuracy based on the referenced standards, this tool should not be used as the sole basis for manufacturing, engineering, or safety-critical decisions. Users are strictly advised to consult the official, original standard documents published by ISO and ASME for definitive specifications. The developers assume no liability for errors, omissions, or misuse of this information.
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