Put/call ratio: what it measures and what it does not
The put/call ratio is the number of puts traded (or held) for every call. It is easy to compute, widely published, and routinely over-interpreted. Here is what it measures, the two versions that get confused, and how to read it next to the expected move without fooling yourself.
Two ratios, not one
Volume put/call divides today's put volume by today's call volume. It measures what was traded in the session and swings sharply from day to day.
Open interest put/call divides outstanding put contracts by outstanding call contracts. It measures what positions are being held and moves slowly.
They answer different questions. A volume ratio of 1.5 on a day when the open interest ratio is 0.6 means a burst of put buying into a book that is still call-heavy. Reading one without the other is how people end up "bearish" on a stock where nobody is actually positioned bearishly. OptionsMovement blends the two for each expiry and shows the blended figure next to the range.
The 0.7 / 1.2 rule and where it fails
The retail rule of thumb says below 0.7 is bullish (more calls), above 1.2 is bearish (more puts), and extremes are contrarian. As a starting point for single stocks it is fine. It fails in three common cases:
- Index products. SPX, SPY and QQQ puts are bought as portfolio insurance by institutions who are long the market. A put/call ratio above 1.5 on SPY is normal and says nothing bearish; it says funds are hedged.
- Stocks with heavy covered-call programs. Persistent call selling by holders inflates call open interest and makes the stock look permanently bullish.
- Any single day. One large spread order can move the volume ratio from 0.5 to 1.5 and back. A spread that buys 10,000 puts and sells 10,000 lower puts is not "bearish" 20,000 contracts; it is a defined-risk hedge.
Reading it next to the expected move
The put/call ratio is a sentiment gauge; the expected move is a size gauge. Together they describe the chain:
| Expected move | Put/call | What it usually means |
|---|---|---|
| Wide | High | Fear: a big move is priced and traders are leaning on the downside. Common into earnings on a stock that has disappointed before. |
| Wide | Low | Speculation: a big move is priced and traders want the upside. Common in momentum names and takeover chatter. |
| Narrow | High | Quiet hedging: nobody expects much, and the puts are insurance rather than a bet. |
| Narrow | Low | Complacency, or simply a boring stock. Worth noting when it coincides with a scheduled event. |
As a contrarian indicator
The contrarian reading, where an extreme ratio marks a turning point, has the best record on broad measures such as the CBOE total put/call ratio, and mainly at multi-week extremes. On a single stock over a single expiry it is much weaker, because the "crowd" whose positioning you are fading may be one fund's hedge. Treat a single-stock extreme as a prompt to look at the open interest by strike (the support and resistance figures on the calculator) rather than as a signal on its own.
What it does not do
It does not predict direction on its own, it does not size a move (that is the expected move's job), and it does not distinguish between opening and closing trades, or between buyers and sellers. A put that was sold to open counts the same as a put that was bought to open, and they mean opposite things. Only a broker's own flow data can separate those, which is why "unusual options activity" services exist and why their signals are noisy too.
Practical use
Note the ratio when the expected move is unusually wide or narrow for the stock; it tells you which side of the range the crowd is worried about. Check the open interest ratio, not just the volume ratio, before calling anything a trend. And on index products, ignore the 0.7 / 1.2 rule entirely and compare today's ratio with the product's own recent average.