In one embodiment, a method includes receiving a search query from a user of an online social network and searching multiple verticals to identify multiple sets of objects in each vertical, respectively, that match the search query, and wherein each vertical stores one or more objects associated with the online social network. The method also includes ranking, for each set of identified objects from a vertical, each identified object in the set of identified objects. The method further includes blending the multiple sets of identified objects from each vertical to form a set of blended search results that includes a threshold number of identified objects, the blending including an iterative process performed at least the threshold number of iterations. Each iteration of the iterative blending process includes determining a blender score for each top-ranked identified object in each set of identified objects.