No key, API key, or OAuth?
The authentication type tells you what must happen before calling an API. Learn the differences, when to use each method, and how to start without exposing credentials.
No key
The quickest route: send a request to the endpoint and receive the response.
279 APIs in the catalog
When to choose it
Prototypes, learning, public data, and integrations that do not access personal information.
How it works
- 1.Copy the endpoint or curl command.
- 2.Send the request.
- 3.Read the JSON response.
Remember
There are no secrets to protect, but per-IP limits and terms of use still apply.
API key
A key identifies your project and lets the provider measure its usage.
218 APIs in the catalog
When to choose it
Weather, AI, search, data, and developer services offering a free tier after signup.
How it works
- 1.Create an account with the provider.
- 2.Generate a key.
- 3.Send it in the header or parameter specified by the documentation.
Remember
Keep the key on the server; never place it in browser code, a public repository, or a shared URL.
OAuth
A user authorizes your app to access part of their account without sharing a password.
54 APIs in the catalog
When to choose it
Integrations with personal accounts such as Google Drive, GitHub, Spotify, or workplace tools.
How it works
- 1.Register your app and redirect URL.
- 2.Send the user to the consent screen.
- 3.Exchange the returned code for a limited-permission token.
Remember
Request only necessary scopes, protect client secrets and refresh tokens, and handle expiry and revocation.