P/E Ratio (Price-to-Earnings) — Stock Market Glossary
P/E Ratio — Price-to-Earnings Ratio
The P/E ratio (Price-to-Earnings ratio) is the most widely used stock valuation metric. It tells you how much investors are willing to pay for each dollar of a company’s earnings.
Formula
P/E Ratio = Stock Price ÷ Earnings Per Share (EPS)
Example: A stock trading at $100 with earnings of $5 per share has a P/E ratio of 20 — investors are paying $20 for every $1 of earnings.
How to Interpret P/E
| P/E Range | Typical Interpretation |
|---|---|
| < 10 | Low/cheap — may be undervalued or a declining business |
| 10–20 | Moderate — average historical range for large-cap stocks |
| 20–30 | Growth premium — market expects strong earnings growth |
| > 30 | High valuation — common for high-growth tech; risky if growth slows |
| Negative | Company is losing money (no meaningful P/E) |
Trailing vs. Forward P/E
- Trailing P/E (the standard P/E shown here) uses the most recent 12 months of actual earnings
- Forward P/E uses analysts’ estimates of future earnings — useful for growth companies
Industry Comparisons Matter
P/E ratios vary widely by industry. A P/E of 12 is normal for utilities; the same P/E for a software company would be extremely cheap. Always compare P/E to industry peers, not just the absolute number.
How It’s Used on This Site
P/E ratio appears in the Market Data card on every ticker page. It’s shown alongside Forward P/E to give both a current and forward-looking picture.
The 🐋 Institutional Whale strategy targets large, established companies that often have moderate, stable P/E ratios — the kind institutional investors gravitate toward.
Related Terms
- Forward P/E — Future-looking earnings estimate
- EPS — The earnings component of P/E
- Price-to-Book — Valuation relative to assets, not earnings
- Market Capitalization — Size context for P/E comparison
Data on this site is for educational purposes only and does not constitute financial advice.