A topic-centric list of high quality open datasets.

Data.gov is the United States government's open data website. It provides access to datasets published by agencies across the federal government. Data.gov is intended to provide access to government open data to the public, achieve agency missions, drive innovation, fuel economic activity, and uphold the ideals of an open and transparent government.

A search engine for datasets.
Using a simple keyword search, users can discover datasets hosted in thousands of repositories across the Web.
Dataset Search primarily indexes dataset pages on the Web that contain schema.org structured data. The schema.org metadata allows Web page authors to describe the semantics of the page: the entities on the pages and their properties.

"246k high-quality public datasets. Everything from avocado prices to video game sales."
Kaggle supports a variety of dataset publication formats, but they strongly encourage dataset publishers to share their data in an accessible, non-proprietary format if possible. Not only are open, accessible data formats better supported on the platform, they are also easier to work with for more people regardless of their tools

re3data is a global registry of research data repositories.
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