What Is P/E Ratio? (Price-to-Earnings) Explained

The P/E ratio (price-to-earnings ratio) is the most widely used valuation metric in stock investing. It tells you how much investors are paying for each dollar of a company's earnings.

P/E Ratio = Stock Price ÷ Earnings Per Share (EPS)

Example: A stock at $100 with EPS of $5 has a P/E of 20. That means investors are paying $20 for every $1 of annual earnings.

How to Interpret the P/E Ratio

• High P/E (25+): Investors expect strong future growth. Common in tech and growth stocks. Risky if growth disappoints.
• Moderate P/E (15–25): Typical for the broad S&P 500 historically.
• Low P/E (below 15): May indicate undervaluation, or may signal a declining business. Always investigate why.

Trailing P/E vs. Forward P/E

Trailing P/E uses the last 12 months of actual earnings. Forward P/E uses analyst estimates for the next 12 months. Forward P/E is generally more useful because stocks are priced on future expectations, not the past.

P/E Ratio by Sector

P/E ratios vary significantly by sector. Technology stocks often trade at 25–35x earnings. Utilities and financials often trade at 10–15x. Always compare a stock's P/E to its sector peers, not just the market average.

P/E Limitations

P/E ignores growth rate (see PEG ratio for that), doesn't work for companies with negative earnings, and can be distorted by one-time charges. Use it alongside other metrics.

See the PEG ratio rankings for stocks with the best growth-adjusted valuation, or today's AI picks which include P/E in their analysis.