Put/call ratio

The ratio can be calculated on trading volume over a period or on open interest at a moment in time. A value below 1 means more calls than puts are traded or held, and a value above 1 means puts dominate. Crypto data providers publish it for bitcoin and ether options, often split by expiry.

Traders use it as a sentiment indicator. A low ratio suggests speculative appetite for upside, while a rising ratio shows that more participants are paying for downside protection. Some read extremes contrarily: very heavy put buying can appear near local bottoms, when fear is already priced in.

The ratio counts contracts, not intent. A put can be a bearish bet or a hedge on a large spot holding, and a call can be sold rather than bought. Comparing it with skew, funding rates and positioning data gives a far more reliable picture than reading the number on its own.