What is the P/E ratio (price-to-earnings)?

The P/E ratio divides a stock's current share price by its trailing twelve-month earnings per share — how many dollars investors are paying today for one dollar of the company's annual earnings.

Is a high P/E always expensive, and a low P/E always cheap?

No. A high P/E can mean the market expects fast earnings growth, or it can mean the stock is simply overpriced relative to its actual prospects — the ratio alone can't tell you which. A low P/E can mean genuine value, or it can mean the market correctly expects earnings to fall. P/E only becomes informative compared against a company's own history, its sector peers, and its expected growth rate.

Live example: AAPL's current P/E ratio is 34.1 — in the broad average range for a large-cap stock. See the full AAPL forecast for how this fits its fundamentals profile alongside the quantum model's own price forecast.

What P/E doesn't capture

P/E says nothing about debt levels, cash flow quality, or whether reported earnings were boosted by one-time items. A company can have an attractive P/E while carrying financial risk that a metric like debt-to-equity would reveal instead — it's one input among several, never a standalone signal on its own.

Frequently asked questions

What counts as a good P/E ratio?

There's no universal good P/E — it depends on the sector and the company's growth rate. A P/E that's cheap for a mature utility could be expensive for a slow-growth industrial.

Why do growth stocks have higher P/E ratios?

The market is pricing in earnings growth expected in future years — investors are paying up front for profits they expect the company to earn later.

Can P/E be negative or meaningless?

Yes — a company with negative trailing earnings has an undefined or negative P/E, which is why loss-making growth companies are usually valued on revenue multiples instead.

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AAPL analysis shows this metric in context, or browse all S&P 500 tickers.

Related terms

Educational research only — not investment advice.