What does the price-to-earnings ratio compare for a publicly traded company?

The price-to-earnings ratio compares a publicly traded company’s share price with its earnings per share.

The ratio, commonly abbreviated P/E, is calculated by dividing the market price per share by earnings per share. It gives investors a way to relate what the market pays for a share to the company’s reported profit attributable to each share.

A higher P/E can reflect expectations of stronger future growth, but it can also indicate that a share is expensive relative to current earnings. A lower P/E may signal lower growth expectations, cyclical conditions, or a potentially cheaper valuation. The number alone does not prove that a stock is overvalued or undervalued.

Analysts distinguish trailing P/E, based on past earnings, from forward P/E, based on forecast earnings. Comparisons are most useful between companies in similar industries because growth rates, accounting practices, and business cycles differ.