Google Dataset Search enables users to find datasets stored across thousands of repositories on the Web, making these datasets universally accessible and useful.
UNData contains over 55 million data points covering a wide range of themes including Agriculture, Education, Employment, Energy, Environment, Health, HIV/AIDS, Human Development, Industry, Information and Communication Technology, National Accounts, Population, Refugees, Tourism, Trade, as well as the Millennium Development Goals indicators.
The purpose of Data.gov is to increase public access to high value, machine readable datasets generated by the Executive Branch of the Federal Government. Contains a Raw Data Catalog of reports and data from various government agencies, a Tool Catalog, and a Geodata Catalog.
SimplyAnalytics is a web-based mapping, analytics and data visualization program providing data variables. Users have access to demographics, marketing data, consumer behavior (purchasing and product usage data), market segments, health, and business points for States, Congressional Districts, Counties, Cities/Places, ZIP Codes, Census Tracts and Block Groups. Users can also export data, maps, reports and shapefiles for use outside of SimplyAnalytics. Now includes Nielsen Scarborough Data Module.
Users are not required to log-in with a user name and password; however, in order to save your work, it is recommended that you create your own user account. SimplyMap user accounts are still functional in the SimplyAnalytics interface.
The European Data Portal harvests the metadata of Public Sector Information available on public data portals across European countries. Information regarding the provision of data and the benefits of re-using data is also included.
DataCite
Datasets across over 1000 different major data centers and repositories including ICPSR, Harvard Dataverse, Data-Planet, the California Digit.
Data.World
Find open data about open data contributed by thousands of users and organizations across the world.
Kaggle data science community