Abstract: An online system receives a content item and budget for presenting the content item from a publishing user, and estimates certain interactions by users presented with the content item if the budget is increased. The online system applies one or more models to the received budget to estimate one or more interactions with the content item for different increased budgets. The online system presents the estimated interactions and different increased budgets to the publishing user. To encourage the publishing user to increase the budget, the online system may present estimated interactions by users corresponding to different increased budgets when the publishing user provides the content item to the online system. The online system may limit presentation of estimated interactions for increased budgets to increased budgets for which the online system estimated interactions with at least a threshold accuracy and may identify an increased budget optimizing a number of estimated interactions.