1. A computer-implemented method comprising: storing, by an online system, a set of user profiles describing users of the online system, each user profile comprising one or more user attributes describing a user; receiving, by the online system, information identifying an input content item for sending to users of the online system; configuring a first user interface to a client device, the first user interface configured to receive a target audience criteria for selecting users for receiving the input content item, the first user interface comprising a widget for mapping a user attribute to a set of values; sending the first user interface to the client device; receiving, via the first user interface a target audience criteria; identifying one or more content attributes describing the input content item; determining a plurality of subsets of values of the user attribute, each subset of values associated with a set of users having a value from the subset of values for the user attribute; configuring a second user interface comprising a plurality of widgets, each widget associated with a subset of values of the user attribute, the second user interface displaying in connection with the widget, a measure of interest of users of the subset of users in the input content item, wherein the measure of interest is determined as a value inversely related to the number of past interactions with a matching content item indicating a dislike towards the matching content item, wherein the matching content item has content attributes matching content attributes of the input content item; sending the second user interface to the client device; receiving, via one or more widgets from the plurality of widgets of the second user interface, a selection of a subset of values; determining a modified target audience criteria based on the selected subset of values; and distributing the input content item to users selected based on the modified target audience criteria.