As others have said it depends on what your site is about. If your site already exists there isn't much you can do but if you are planning to create a site then you can find out what the CPM average is by using Google Adword tools to find out how much people are paying for the key words. That will give you a fairly good idea of what you can charge. As others have already said you will make more money if you sell adds yourself but I would only budget two or three times the price not ten or one hundred times markup.<br><br> Also a pure add model isn't generally the best idea. If you link to a realted product you can often get comissions that are much higher than the CPM average that you will get for adds. Without context you can only assume that you will get $0.15 CPM. Social networking sites are probably slightly less.