P/E Ratio (Price-to-Earnings)

A stock's current price divided by its earnings per share (EPS) over the trailing twelve months.

P/E Ratio (Price-to-Earnings) — A stock's current price divided by its earnings per share (EPS) over the trailing twelve months.

Key facts

Category
Valuation
Definition
A stock's current price divided by its earnings per share (EPS) over the trailing twelve months.
Formula
P/E = Current share price / Earnings per share (TTM)
Live example
/research/stock/AAPL
Last updated
2026-06-17

Formula

P/E = Current share price / Earnings per share (TTM)

Worked example

If Apple trades at $200 per share with trailing-12-month EPS of $6.50, its P/E is $200 / $6.50 = 30.8 — meaning investors are paying $30.80 for every $1 of current earnings.

Interpretive bands

P/E < 15
Mature or undervalued. Common for banks, utilities, telcos, and out-of-favour cyclicals.
P/E 15 – 25
Market-average range. Typical for stable, profitable large-caps without exceptional growth.
P/E > 25
High growth expected. Investors are paying for future earnings, not current ones.
P/E negative or N/A
Company is unprofitable on a trailing basis. The metric stops being meaningful.

How IndexAlpha uses P/E Ratio (Price-to-Earnings)

Every IndexAlpha research page surfaces P/E on the Valuation card, color-coded against the stock's sector peers — so you see whether AAPL's P/E is high vs other technology stocks specifically, not just vs the market.

See it live

The P/E Ratio (Price-to-Earnings) metric shows up on every IndexAlpha research page. See it now on AAPL — or research any stock to view its P/E Ratio (Price-to-Earnings).

Related terms

Common questions

Is a low P/E always good?

No. A low P/E can mean undervalued, or it can mean the market expects earnings to fall. Always compare P/E against sector peers and growth outlook — a P/E of 8 on a coal miner with declining revenue is very different from a P/E of 8 on a growing regional bank.

Why do tech stocks have higher P/E ratios?

Investors price tech stocks on future earnings, not current ones. A software company doubling revenue annually will have a high trailing P/E that looks reasonable on forward (projected) earnings. Compare tech P/Es against forward earnings, not just trailing.

What's the difference between P/E and forward P/E?

P/E uses trailing-twelve-month (TTM) actual earnings. Forward P/E uses analyst-projected earnings for the next 12 months. Forward P/E will usually be lower if growth is expected — but it relies on forecasts that can be wrong.

Sources