Calculate the Price-to-Earnings ratio for any stock. Compare trailing and forward P/E, understand valuation context, and evaluate if a stock is overvalued or undervalued.
The Price-to-Earnings (P/E) ratio is the most widely used stock valuation metric in the world. It tells you how much investors are willing to pay for each dollar of a company's earnings, making it a quick gauge of whether a stock is cheap, fairly valued, or expensive relative to its earnings power.
Our PE Ratio Calculator computes both trailing P/E (based on past 12 months of earnings) and forward P/E (based on estimated future earnings). It also shows the earnings yield — the inverse of P/E — which makes it easy to compare stock valuations to bond yields and other asset classes.
A low P/E may signal a bargain — or a company in trouble. A high P/E may indicate overvaluation — or a high-growth company worth the premium. Context is everything, and this calculator gives you the numbers to start the analysis. Comparing P/E across sector peers and historical averages highlights relative value more reliably than looking at any single number in isolation.
P/E is the common language of stock valuation. Whether you are comparing two companies in the same industry, evaluating a stock against its historical average, or deciding if the market is expensive, the P/E ratio is where the conversation starts. This calculator makes the math instant so you can focus on interpretation.
P/E Ratio = Stock Price / Earnings per Share. Earnings Yield = EPS / Price × 100 (inverse of P/E). PEG Ratio = P/E / Annual EPS Growth Rate.
Result: Trailing P/E: 26.9, Forward P/E: 22.4, Earnings Yield: 3.7%, PEG: 1.8
A stock at $175 with $6.50 trailing EPS has a P/E of 26.9 — above the S&P 500 average of ~22. The forward P/E of 22.4 (based on $7.80 estimated EPS) is more reasonable, suggesting analysts expect earnings growth. The PEG ratio of 1.8 indicates the stock may be slightly overvalued relative to its 15% growth rate (PEG of 1.0 is considered fair).
When the overall market P/E is high, it often signals elevated valuations — but not necessarily an imminent crash. The market traded at a trailing P/E above 20 for most of the 2010s and continued to rise. P/E is a valuation compass, not a timing tool.
Technology companies routinely trade at P/Es of 25-40 because investors expect rapid earnings growth. Banks and utilities trade at 10-15× because growth is slower and more predictable. Comparing a tech stock's P/E to a utility's is meaningless — always benchmark within the same industry.
P/E can be distorted by one-time charges, accounting adjustments, or cyclical earnings peaks. The Shiller CAPE ratio (cyclically adjusted P/E) smooths these issues by averaging 10 years of inflation-adjusted earnings. For cyclical industries like energy or materials, normalized earnings provide a better valuation benchmark than a single year.
There is no universal "good" P/E. The S&P 500 average is historically about 15-17, currently around 22. Growth stocks often trade at 30-50× or higher. Value stocks trade at 8-15×. Compare to sector peers and the stock's own historical range for context.
Trailing P/E uses actual earnings from the past 12 months. Forward P/E uses analyst estimates for the next 12 months. Forward P/E is more relevant for fast-growing companies whose past earnings understate future profit potential.
Technically yes, when a company has negative earnings. However, a negative P/E is not meaningful for valuation purposes. Investors use alternative metrics like price-to-sales, price-to-book, or enterprise-value-to-revenue for unprofitable companies.
A high P/E means investors are paying more per dollar of earnings, typically because they expect strong future growth. However, it can also mean the stock is overvalued. Compare the P/E to the company's growth rate (PEG ratio) to distinguish between justified and excessive premiums.
PEG divides the P/E by the expected annual EPS growth rate. A PEG of 1.0 is considered fair value — you are paying a P/E equal to the growth rate. Below 1.0 may be undervalued; above 2.0 may be expensive relative to growth.
Earnings yield is simply 1 divided by P/E, expressed as a percentage. A P/E of 20 equals a 5% earnings yield. This inversion lets you compare stock valuations to bond yields: if a stock yields 5% on earnings and a bond yields 4%, the stock may be more attractive.