P/S Ratio (Price-to-Sales)
How many times annual sales the market cap is — used to value growth companies with little or no profit.
In plain terms
P/S looks at how many times one year of sales the whole company is worth (its market cap). The key is that it uses sales, not earnings, as the yardstick.
For example, a company with $1B in sales and a $5B market cap has a P/S of 5. Even a loss-making early-stage company has sales, so you can still gauge value relative to scale.
What it tells you
Early-stage or aggressively investing growth companies deliberately suppress earnings (pouring money into R&D and marketing), which makes P/E meaningless. P/S lets you see the market's "valuation relative to top line" for such companies.
P/S indirectly captures the market's expectation of what margin (net profit) those sales will eventually turn into. For the same revenue, a company expected to keep more later gets a higher P/S.
Formula
P/S = market cap ÷ revenue (TTM)
What high or low means
A low P/S can mean the stock is low relative to sales; a high P/S reflects big expectations for future revenue growth or margin expansion.
Low-margin industries (retail, wholesale) earn little from the same sales, so a low P/S is normal there. You must compare within the same industry.
P/S's biggest weakness is that it ignores how much the company keeps (margin) entirely. A company piling up losses despite huge sales and one that keeps a fat margin on the same sales can show the identical P/S. So always read P/S with net margin and operating margin.
P/S is often used instead of P/E for high-growth, loss-making companies — but the very fact that there are no earnings and only P/S works can itself be a warning sign. If sales grow fast but cash keeps draining, a low P/S is no comfort (check cash flow and FCF).
How sales are recognized differs by industry and company. Brokerages and platforms may book the entire transaction value as revenue, so an identical-looking P/S can hide very different revenue "quality."
During the dot-com bubble, Sun Microsystems traded at a P/S above 10. After the bubble burst, its CEO Scott McNealy became famous for turning a question back on investors in an interview.
"A P/S of 10 means that even if I gave you every dollar of revenue for 10 years and spent nothing, you would just break even. For that, employee pay, taxes, and R&D all have to be zero. What were you thinking buying at that price?" It is a famous anecdote showing the limits of P/S — how dangerous it is to pay a high price on sales alone.
Metrics to read alongside
See it in real stocks
Search US stocks on Stocklore to see P/S and other financial metrics alongside the sector benchmark.
This explanation is for information and reference only and is not a recommendation to buy or sell any security. Investment decisions and their consequences are your own.