The price to book(PB ratio), also known as just PB, is a ratio used to compare a company's market price to its book price. A company's book value is any value recorded on its books. It is visible on Yahoo Finance under Statistics Valuation Measures of a company's page. It is calculated by dividing the market value per share of a company by the book value per share. For instance, if Company A has a market value per share of $50 and a book value per share of $52, its PB is 0.96. Value-oriented investors use PB to identify potential investments. Value investing entails investing in companies that are trading for less than their book value. A PB less than one is considered a good investment, indicating that the company is undervalued. Company A, which has a PB of 0.96, is a good investment.