Abstract: Techniques for conducting A/B experimentation of online content are described. According to various embodiments, a user specification of targeting criteria defining a targeted segment of members of an online social networking service for an A/B experiment is received. A set of members of the online social networking service satisfying the user-specified targeting criteria is then identified. Thereafter, a user specification of allocation criteria defining one or more variants of an A/B experiment and one or more corresponding allocation percentages is received. A subset of the set of members (corresponding to the user-specific allocation percentage associated with the respective user-specified variant) is then assigned to each of the user-specified variants. Further, at least one data record associated with each of the variants is recorded in a database, each data record indicating the subset of the set of members assigned to the respective variant.