The Betfair API provides an alternative interface to the Betfair Betting Exchange. It enables developers to create applications that integrate with Betfair. There are two versions of the Betfair API, one for Sports, the other for Games. These can be for:
When developing programs for your own personal use, it is most likely you'll want to use the free version of the API. This allows you to access the majority of the function calls within the API, but limits are imposed as to the number of calls you can make to most of the functions. Unless you intend developing an application that will make a lot of calls to the API, this will likely be the only version you'll need.
There is no need to sign-up to the free access API, you just need to follow the guidelines set out on the Betfair site. The only condition they apply is you need to have an active Betfair account to use the free access Betfair API.
For a Betfair account to be considered 'active', you need to make at least one transaction (settled bet, deposit, withdrawal) within the last three months.
Betfair provide no direct developer support with the free access API, but you get access to their developer forum and they also provide sample code for a number of different programming languages, such as php, java, c# and visual basic, which offer a great way to get you started.
If you are developing your own applications and have a need to make call to API functions not available within the free access API, you'll need to subscribe to the full access version (it is unlikely you'll need full access if you are just starting out developing a Betfair API application).
To access the full version, you need to pay a monthly subscription fee, but there are no restrictions on the number of call you can make to the API functions (within reasonable limits). In addition to the monthly subscription fee, there can be additional data request fees, based on usage.
If you want to build software that utilises the Betfair API and offer it to other users (either for free or payment) you need a software vendor license. There are two types of vendor license available, depending upon whether the software you develop will utilise the free access API or the full access API.
There is no subscription free to pay if you are just developing software that will access the free API, but a monthly access free is charged for the full API.
If you are distributing historical Betfair data, or tools that build a historical prices database, you will need to obtain an historical data license from Betfair.
When you access the Betfair site it not immediately obvious how you access the Betfair Developers area. At the foot of the Betfair Home Page click where it says "Developers Program". There you'll find all the information you need to get started developing applications to access the Betfair API.
If you are not a programmer or you do not have the time to develop your own Betfair API program, there are plenty of options available to you. Within the developers program, Betfair provide a directory of 3rd party software and API developers, designed to improve your productivity on Betfair.