Advertisements are a common way to increase the revenue for websites. All users, however, are not interested in exposing themselves to advertisements and instead avoids it by installing an ad-blocker extension to their browser. In this thesis, a data collection followed by an analysis of the created dataset has been performed, with the purpose of identifying possible user integrity issues when using the ad-blocker extensions AdBlock and Adblock Plus. The study focuses on what kind of advertisements are displayed to a user and if it depend on the used ad-blocker extension or lack thereof, regional location, and the used browser. The data collection was carried out using a Selenium-based data collection tool, which both impersonated a real user surfing the Internet and scraped data from the visited websites along the way. The data collection was performed during a period of 21 days, using five different fictional users. A critical part of the thesis has been to find out how well user profiling, in the context of distributing targeted advertisement, works depending on if an ad-blocker extension is utilized or not. The used tool visited around 162 unique URLs per session and day, resulting in a dataset for further analysis. It was concluded that few differences in the number of targeted vs. untargeted ads a user was exposed to occurred in relation to regional location and used browser. The amount of advertisement decreased with the use of an ad-blocker, however, the data indicated that the share of targeted ads, compared to untargeted, increase with the use of an ad-blocker extension.