Put/call ratio (P/C ratio)

The put/call ratio divides the number of puts traded (or held as open interest) by the number of calls, for the market as a whole or for an individual name. It can be built two ways: from a single day's volume, which shows what's actively trading right now, or from open interest, which shows the standing positioning built up over time. Both versions are read the same way, just on different time horizons. Volume for today's flow, open interest for the accumulated position.

A ratio above 1.0 means puts are outtrading calls, generally the more bearish-leaning side, since it implies more hedging or bearish speculation relative to bullish activity. A ratio below 1.0 means calls dominate, the more bullish-leaning reading. It's also commonly used as a contrarian gauge at extremes. A put/call ratio running unusually high across the whole market has historically coincided with periods of excessive fear, which some traders read as a setup for a bounce, and the mirror-image extreme low ratio with excessive optimism.

The ratio doesn't distinguish why puts or calls are being traded. A rising ratio driven by institutions buying protective puts against long stock positions looks identical in the math to one driven by outright bearish speculation, even though the two imply very different things about market conviction. It's also easy to misread the direction of the number itself, since the ratio is genuinely counterintuitive on first glance (higher number, more bearish, when many people's first instinct is the opposite), and it says nothing about which specific names or sectors are driving an aggregate market-wide reading. A single large hedge from one institution can move the whole-market number for a session without reflecting any broader shift in how traders across the market are actually positioned.

Take a session where the market-wide put/call ratio by volume reads 0.55, calls outtrading puts by roughly two to one, the bullish-leaning side. A separate session reads 1.15, where puts now outtrade calls by a small but real margin. The second session reflects meaningfully more hedging or bearish positioning than the first, even though neither number alone says whether that positioning is protective hedging by funds already long stock, fresh bearish speculation, or some mix of both, a distinction the ratio itself cannot make.