I was searching for a list of states of every country yesterday. There are some API projects help to reveal the currency, latitude/longitude, languages and time-zone of different countries. However, there are rarely free and simple APIs generating lists of states. So I made one!
And here is the LINK
2. [Simple to use]
To use it, simply enter the 2-characters alpha2-code at the end of the link.
For example, United States is "us", Australia is "au", Hong Kong is "hk".
Rendering the page, you will see a list of states in that country presented in JSON format.
Hope you will find it useful!