IEEE's online repository for datasets and data analysis tools. Some data sets are open access, but others can only be accessed if the user has an individual subscription.

Standard Reference Data (SRD) in Chemistry, Engineering, Fluids and Condensed Phases, Material Sciences, Mathematical and Computer Sciences and Physics produced by NIST. This is a mix of 49 free SRD databases and 41 fee-based SRD databases.

Data on Engineering and Science education and research expenditures and outcomes. Includes earned doctorates, higher ed R&D, federal funds for R&D and support to institutions, research, facilities, national survey of college graduates, and IPEDS enrollment and completion.

Public datasets for machine learning projects. "Everything from avocado prices to video game sales."

Free datasets from Microsoft Research to support research in areas such as natural language processing, computer vision, and domain specific sciences.

The SNAP library collects large social and information networks datasets that have been scraped for research purposes. It includes a Microsoft Instant Messenger network from 2006 with 240 million nodes and 1.3 billion edges.

Contains the calculated properties of over 200,000 Open molecules provided by the US National Cancer Institute (NCI). Properties include heat of formation, 3-dimensional structure, dipole moment and ionization potential.

Searchable database of material properties. Includes data sheets of thermoplastic and thermoset polymers such as ABS, nylon, polycarbonate, polyester, polyethylene and polypropylene; metals such as aluminum, cobalt, copper, lead, magnesium, nickel, steel, superalloys, titanium and zinc alloys; ceramics; plus semiconductors, fibers, and more.