Free APIs by feature

Free APIs grouped by what they offer: no key needed, a free key, JSON or XML responses, SOAP, or open source code. The lists update themselves as services are added.

Free APIs with no key

These free APIs work without an API key, a sign-up or an account: you can call them straight from your code, a script or the browser. They…

Free APIs with a free API key

These APIs need an API key, but the key is free: sign up, get a key and call the API within the limits of the free plan. A key usually…

Free JSON APIs

These free APIs answer in JSON, the format that JavaScript, Python, PHP and almost every other language read without extra work. Use them…

Free XML APIs

These free APIs and web services answer in XML (some also in JSON). XML is still common in enterprise software, in RSS and Atom feeds and…

Free SOAP web services

Free SOAP web services, described by a WSDL file, that you can call from .NET, Java, PHP or any other SOAP client. Useful to learn SOAP or…

Free open source APIs

These free APIs are open source: besides the public service, the code is available, so you can read how it works and, if the public server…