Bitcoin open interest to market cap ratio: aggregated BTC futures open interest across all tracked exchanges divided by market cap. High leverage relative to the size of the market has preceded violent unwinds. Daily since 2020.
Left axis: BTC price (log). Right axis: aggregated futures open interest as % of market cap (supply from the issuance schedule).
OI / market cap = aggregated futures open interest (USD) / (close × circulating supply)
Open interest is the dollar value of all outstanding BTC futures and perpetual contracts across the exchanges Coinfuty tracks, taken from the daily close of the aggregated open-interest series. Market cap is the daily close multiplied by circulating supply computed from the issuance schedule, so the ratio is fully reproducible and does not depend on a third-party market-cap feed.
Dividing by market cap normalises leverage for the size of the market: $40B of open interest meant far more in 2021 than it does today.
The ratio measures how much of the market is expressed through leverage. It climbed above 4% ahead of the deleveraging events of 2021 and 2022, and readings near the threshold have tended to precede sharp liquidation-driven moves in either direction. A rising ratio with flat price means positioning is building without conviction; a falling ratio after a spike marks a completed unwind.
2.46% as of Oct 19, 2026 — below the 4% level that marks stretched leverage.
A large share of the market is held through leveraged futures. Leverage cuts both ways: it fuels the final leg of an advance and it forces the liquidations that end it, so high ratios precede volatile unwinds rather than pointing in one direction.
Raw open interest grows with the market. Normalising by market cap makes 2021 and today comparable: the same dollar amount of contracts is far less leverage in a market three times larger.
Every futures exchange Coinfuty tracks, aggregated at the coin level. Open interest counts both sides of each contract once, in USD.
Coinfuty computes every series on this page from daily BTC close prices and public constants — the Bitcoin halving schedule, block subsidy and published regression coefficients. Values refresh nightly (00:20 UTC) and the current day is patched hourly. These are historical, backward-looking indicators; nothing here is investment advice.