Market capitalization is the simplest method of business valuation. It is calculated by multiplying the company's share price by its total number of shares outstanding. For example, as of January 3, 2018, Microsoft Inc. traded at $86.35.2 With a total number of shares outstanding of 7.715 billion, the company could then be valued at $86.35 x 7.715 billion = $666.19 billion.