A method for blocking content from being presented at a client device based on a user profile and content tags. Content having descriptive tags is delivered to a client device from a server device. The descriptive tags classify the content. A user profile at the client device contains tag data for identifying categories of content that the user does not want presented on the client device. The client device recognizes and evaluates the tags of received content and blocks content based on the user profile. The blocked content will not be presented to the user. The user profile may be created automatically or manually by the user. The user profile is automatically created based on usage history or demographic information. The client device has a tag dictionary that may be updated to correspond to tags utilized by content delivery systems.