Calculate the Price-to-Earnings ratio to evaluate whether a stock is overvalued, undervalued, or fairly priced. Includes Forward P/E, PEG ratio, and industry benchmarks.
Try an example:
Optional: Advanced Metrics
Enter stock price and EPS to see your P/E ratio calculation.
The Price-to-Earnings (P/E) ratio is one of the most widely used metrics for stock valuation. According to the CFA Institute, the P/E ratio measures how much investors are willing to pay for each dollar of a company's earnings. A higher P/E suggests investors expect higher earnings growth in the future, while a lower P/E may indicate the stock is undervalued or that investors have lower growth expectations.
The P/E ratio helps investors compare valuations across companies in the same industry or against the broader market. However, it should never be used in isolation. Factors like growth rate, profit margins, debt levels, and industry dynamics all influence what constitutes a "fair" P/E for a particular stock. Pairing P/E analysis with intrinsic value analysis helps confirm whether a given multiple is justified by the underlying cash flows.
There are two main types: Trailing P/E (using past 12 months earnings) and Forward P/E (using estimated future earnings). Each provides different insights, and savvy investors often look at both to get a complete picture of a stock's valuation. Income-focused investors also weigh dividend yield alongside P/E when assessing total return potential.
P/E Ratio = Stock Price / Earnings Per Share (EPS)
Stock Price: The current market price per share. This is readily available from any financial website or brokerage platform.
Earnings Per Share (EPS): The company's net income divided by the number of outstanding shares. Use our earnings per share calculator to derive this figure from net income and shares outstanding. You can also find TTM (trailing twelve months) EPS in quarterly earnings reports or financial data providers.
Example: If a stock trades at $100 and has EPS of $5, the P/E ratio is 100/5 = 20x. This means investors are paying $20 for every $1 of annual earnings.
A fast-growing tech company trading at $200 with EPS of $5 has a P/E of 40x. While this seems expensive, if earnings are growing 30% annually, the PEG ratio is 1.33, which is reasonable. Investors accept paying a premium for expected future growth. In 3 years, if earnings double, the effective P/E based on future earnings would be 20x.
A mature utility company trading at $50 with EPS of $5 has a P/E of 10x. The low P/E reflects limited growth expectations (3-5% annually). However, if the company pays a 4% dividend yield and has stable cash flows, it may be attractive for income-focused investors. The low P/E is not a "bargain" but reflects the business reality.
A biotech startup trading at $30 with negative EPS of -$2 has no meaningful P/E ratio. For unprofitable companies, investors use alternative metrics: Price-to-Sales (P/S) ratio, Enterprise-Value-to-Revenue, or analysis of cash runway and pipeline value. The P/E ratio simply does not work for companies not yet generating profits.
While the P/E ratio is a useful starting point, it has significant limitations that investors should understand:
View all Financial Ratio tools → or explore the Investment Analysis hub .
Pair this tool with the Asset Turnover Calculator and the CAC Calculator to cross-check inputs. For strategic context, read our 12-month exit checklist and explore the Financial Ratios tools hub.
Calculate return on investment for any investment type
Measure ability to meet short-term obligations
Calculate current ratio and working capital
Calculate proportion of assets financed by shareholders
Financial Basics Guide
In-depth guide with examples, benchmarks, and interactive calculators