A vast amount of information and knowledge has been accumulated and circulated on the Web. They provide people with options regarding their daily lives and are starting to have a strong influence on governmental policies and business management. A crucial problem is that information on the Web is not necessarily credible. This paper describes an information analysis system called WISDOM, which assists users in assessing the credibility of information on the Web. WISDOM is to organize information on a given topic through the following three types of analyses: (1) extracting and contrasting opinions and important statements around the points related to the topic, (2) identifying and classifying the information sender of each page; and (3) analyzing the appearance of each page, for example, page design and writing style. Our preliminary evaluation indicates the effectiveness of WISDOM and its advantage to Google from the viewpoint of the ability of grasping the difference of information senders and opinions.