PE Ratio Calculator: Price-to-Earnings Analysis

Calculate trailing PE, forward PE, and PEG ratio. See how any stock's valuation compares to the S&P 500 and sector averages.

Last Updated: March 2026

Calculate PE Ratio

Current share price or your entry price
Last 12 months earnings per share
Next 12 months analyst estimate
Annual EPS growth rate for PEG ratio calculation
Enter a stock price and EPS to calculate PE ratios, PEG ratio, and see valuation analysis.

S&P 500 Historical PE Ratio

How the market's valuation has shifted over the past two decades. The long-term average PE is approximately 16-17.

Below Average (<17) Average (17-25) Above Average (>25)

PE Ratio by Sector — Reference Table

Average PE ratios vary significantly by sector. Use this table to benchmark any stock against its industry peers.

Sector Avg PE Median PE PE Range Typical Companies Valuation Notes

PE Ratio Explained: Key Insights

PE Ratio Alone Can Be Misleading

A low PE does not automatically mean a stock is a bargain. Companies with declining earnings, heavy debt, or regulatory headwinds often trade at low PEs for good reason — these are called "value traps." Conversely, a high PE may be justified if a company is growing earnings rapidly. Always pair PE with the PEG ratio, which accounts for growth, and compare against sector averages rather than the broad market.

Forward PE Is Often More Useful Than Trailing PE

Trailing PE reflects the past, but stocks are priced on future expectations. A company that just had a bad quarter may show a misleadingly high trailing PE, while its forward PE (based on expected recovery) tells a more accurate story. The S&P 500 forward PE is typically 1-3 points lower than trailing PE because analysts expect earnings growth. When trailing and forward PE diverge significantly, it signals an inflection point worth investigating.

The PEG Ratio Normalizes Across Growth Rates

Peter Lynch popularized the PEG ratio as a way to compare companies with different growth profiles. A PEG of 1.0 means you're paying a fair price for growth. In practice, PEG under 1.0 is rare for quality companies — it usually appears during broad market selloffs or when a stock is temporarily out of favor. Most S&P 500 growth stocks trade at PEG ratios between 1.0 and 2.5. PEG above 3.0 generally signals overvaluation unless the company has a dominant competitive moat.

Frequently Asked Questions

Methodology

PE ratios are calculated using the standard formula: Stock Price ÷ Earnings Per Share. Trailing PE uses TTM (trailing twelve months) reported EPS. Forward PE uses consensus analyst estimates for the next 12 months. The PEG ratio divides PE by the expected annual EPS growth rate.

Sector average PE ratios are approximate values based on S&P 500 sector indices as of Q1 2026. Historical S&P 500 PE data represents trailing twelve-month earnings. All figures are for educational reference and may not reflect real-time market conditions.

This calculator is for informational and educational purposes only. Not investment advice. PE ratios should be used alongside other valuation metrics. Always do your own research before making investment decisions.