Betfair Data Usage Charges
Posted by Bet Angel - Technical Support on 23 May 2013 10:41 AM
It is important for users of any software (including Bet Angel Professional) to be aware of the data usage policy of Betfair and possible charges that can be incurred. In normal use, Bet Angel obtains data from the Betfair exchange via the Betfair API (Application Programming Interface). This data includes prices, bet details, volume matched, available volume, selection names, times and so on.
Currently, Betfair apply charges if the total number of API calls per second exceed 20 requests in one second.
At the end of every day, we add up the total number of API and website data requests you made in each second and if you made more than 20 data requests in one second we charge you 0.1p per data request above 20.
It is important to note that Website use also contributes to the number of data requests for the purposes of this charge.
In addition, the way Betfair count the number of requests is dependant upon the Betfair server time. It is impossible for this to be synchronised with your local computer time and there may be a discrepancy in the number of calls made per second.
For example, if you have the data request limited to 20 per second in Bet Angel then Bet Angel will not make more than this number of calls per second. However, if Betfair are counting the second from a different starting point then the number of calls may differ according to Betfair.
Please see the below illustration. The yellow row represents the number of requests counted based on the Betfair server time and the green rows represent the data request count made by an application, starting half a second before the second counted by the Betfair server. You can see from the green band that no more than 20 calls per second are made. But Betfair use the timing in the yellow band and the number of calls is exceeding the threshold.
To avoid the charge, we and Betfair recommend the following:
We have asked Betfair to make a tool available to their customers that will monitor data use throughout the day and alert users if the total number of calls is incurring a charge. If you feel this would be of benefit to you also, please email firstname.lastname@example.org to add your support.