Abstract: An online system receives requests to present content to users. The online system adds a code to the content that provides an indication to users that the content may be eligible for compensation when a user interacts with the content and the code directing the user's device to the online system. When the user interacts with the content, the user device accesses the online system, which authenticates the user's identity. Users may then receive a payment or micropayment from the online system for interacting with the content item. The online system may provide such payments for many types of content from various sponsors, such that the online system provides content with a code for various content and permits the online system to preserve user privacy while presenting such content.