What is the P/E ratio?
The price-to-earnings (P/E) ratio is a company's share price divided by its earnings per share. A P/E of 20 means investors are paying $20 for every $1 of annual profit. It is the most common gauge of how expensive or cheap a stock looks relative to the profit the business currently generates.
The P/E ratio matters because it puts price in context. A $500 stock is not automatically expensive and a $5 stock is not automatically cheap; what counts is the price relative to earnings. A higher P/E means the market expects strong future growth; a lower P/E can signal modest expectations, or a business the market is worried about.
P/E is most useful compared with something: the company's own history, its industry peers, or the market as a whole. It has real limits. It is distorted when earnings are temporarily high or low, and it cannot be calculated when a company loses money. For fast growers, the PEG ratio, which weighs P/E against growth, is often more informative.
| P/E range | What it can indicate |
|---|---|
| Low (often below ~15) | Modest expectations, a mature business, or market concern worth investigating. |
| Moderate (~15-25) | Roughly average expectations for a steady, profitable company. |
| High (above ~25) | Strong expected growth, or optimism the results will need to justify. |
Frequently asked questions
Is a high P/E always bad?
No. A high P/E often reflects strong expected growth, and fast-growing companies routinely trade at high multiples. It becomes a risk only if the growth fails to arrive, since the price already assumes it. Comparing with peers and growth rates gives better context.
Why do some companies have no P/E ratio?
If a company has no profit, its earnings are zero or negative, the P/E cannot be calculated, so it is shown as not available. In those cases investors lean on other measures like price-to-sales or free cash flow.