Short answer
Open interest (OI) is the total value of futures contracts still open, meaning not yet closed by an offsetting trade. Rising OI means new positions are opening and falling OI means positions are closing, but OI alone does not show which side is adding. It measures participation and leverage, not direction. For scale, BTC perpetual OI on Binance was about $7.51bn (BTCUSDT, 2026-10-24).
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Key facts
| Definition | Value of all open contracts not yet closed by an offsetting trade |
| OI ↑ | New positions are being opened |
| OI ↓ | Positions are being closed |
| Price + OI together | A hint at which side may be adding, not proof |
| BTC OI on Binance (BTCUSDT, 2026-10-24) | about $7.51bn |
How is open interest different from volume?
Volume counts the contracts traded in a period. Open interest counts the contracts that remain open. A day can have huge volume and unchanged OI if traders only pass positions to each other.
Every open contract has a long on one side and a short on the other, so OI rises only when a new buyer and a new seller open together. That is why OI by itself cannot show direction.
How do I read OI together with price?
Look at the direction of both. Rising OI means new positions are opening, though not who opened them. Some traders read rising price with rising OI as longs adding, and falling price with rising OI as shorts adding. Price rising while OI falls often means shorts are closing rather than new longs arriving. Treat each reading as a guess, and test it against funding and liquidation data before relying on it.
To check the dollar figure, multiply OI in coins by the mark price, or read sumOpenInterestValue directly. On 2026-10-24, BTCUSDT traded near 80,731.7 with OI of about $7.51bn.
Why add funding to the picture?
Funding tells you which side is paying to stay in. When funding is positive, longs pay shorts. When it is negative, shorts pay longs. High OI plus very positive funding points to a crowded, expensive long side. If price stalls, those positions can unwind quickly.
What are the limits of OI?
Each exchange reports its own OI. On Binance, GET /fapi/v1/openInterest returns current OI for one symbol in base units (BTC for BTCUSDT). GET /futures/data/openInterestHist returns history with sumOpenInterestValue, the total open interest value. Both cover Binance only.
Positions can also be hedged on other venues or in spot, so use OI as a gauge of participation and leverage, never as a standalone signal. Leveraged futures can lose more than you expect in a fast move, and no OI reading removes that risk.
What does a sudden drop in open interest mean?
A sudden drop means many positions closed in a short time, though the number alone does not say why. A fast, large fall in OI during a sharp price move usually means positions were forced shut through liquidations or stops. Afterward, leverage is lower and funding often resets toward neutral.
A slow decline over several days more often reflects voluntary closing, for example before a holiday or a scheduled macro event. Compare the speed of the OI change with the price move, and confirm with the exchange's liquidation data.
FAQ
Is rising open interest bullish?
Not by itself. It means more positions are open. It does not tell you whether longs or shorts are doing the adding.
Where can I see open interest?
Exchange contract pages and the Binance public futures data API publish it.
Does OI include spot holdings?
No. It only counts open derivatives contracts.
Why does open interest differ between data sites?
Some sites show one exchange, others add several venues together, and some count in coins rather than dollars, so the totals rarely match exactly.
Sources
Figures change. Check the primary sources below.