What it is
Public APIs is a catalog of free public APIs. The repository groups services by category and usually shows integration details that matter immediately: authentication, HTTPS support, and CORS notes.
The project was created on GitHub in March 2016 and became popular as a fast reference. When you need test data, an endpoint for a side project, or a source for an integration prototype, this list is often faster than generic search.
Catalog entry format
A typical entry includes not just the API name, but practical properties that affect integration.
| API | Description | Auth | HTTPS | CORS |
| --- | --- | --- | --- | --- |
| Example API | Demo public dataset | apiKey | Yes | Unknown |Where it helps
The catalog is useful for prototyping: you can quickly find APIs for weather, finance, geodata, images, entertainment, or developer tooling and decide whether opening the service documentation is worth it.
It is also useful for learning. Public APIs give real network input and output without requiring you to build a backend first.
Limits
The list does not guarantee third-party API stability. Limits, CORS, auth, pricing, and terms change. For production integrations, you still need to read the official documentation for the specific API and check SLA, rate limits, and legal terms.