- American Society for Testing and Materials, ASTM International
- ANSI: American National Standards Institute
- Applications and Heat Treatment of Steels used as Knife Blades
- The Chemical Database Service
- Ceramic Databases
- Engineering ToolBox
Tools and Basic Information for Design, Engineering and Construction of Technical Applications - Fundamental Physical Constants
- Fundamental Physical Constants SI Units
- Materials Science and Engineering Laboratory
- Matmatch
- MatWeb
- Minerals by Name
- National Institute of Standards and Technology (NIST) Databases – Materials Science Portal
- NIST Special Publication 811: Guide for the use of the International System of Units (SI)
- Periodic Table
- Practical Data for Metallurgists – Handbook by Timken
- U. S. Official Time
- VAMAS: THE VERSAILLES PROJECT on ADVANCED MATERIALS and STANDARDS