Below are some of the important version numbers relating to the API. The "Current API Version" is the version of API code that is currently live on the API Servers. The "Development Version" is the version being internally tested. The "Default Call Version" is the schema version that will be assumed if a <Version> tag is absent from an API Call.

What is the difference between API Version and Call Version?

API Version refers to the itteration of code that controls the entire API process, from authentication to parsing, to searching, to returning results. Call Version, on the other hand, refers to the XML Schema accepted by the calls. Call Versions are only updated when there are major changes to the Input or Output schemas of a call, while API Versions may be updated with weekly bug fixes or new features.

When are new versions of the API rolled out to the public?

In general, API Updates will be rolled out on Thursday mornings. If more pressing bugs present themselves, the API will sometimes be hotfixed during the week. There is no downtime associated with updates to the API, so the API is always on.

Where can I see the changes in each version of the API?

Check out the API Updates page.