Google should world’s most valued website and there are so many websites that have a high value. If you have a blog or website you check its worth. Or how many $s you will get paid if you go to sell it. I am talking about monetary value of a website. New and small website has less value old and large websites has more value.
Google, Yahoo, Microsoft, Amazon, Facebook, MySpace and some other are the most valued websites of the world.
These online tools that check worth of a website are not always good and does not provide realistic value. But we cannot blame all the tools, I have tested most of them and tools are worth checking.