# Open Interest > Open interest is the number of futures or options contracts still open. Learn how it differs from volume, how it changes and how traders read it with price. Source: https://learn.tradelabsai.com/markets/open-interest/ Track: Markets and Instruments · Level: Beginner · Updated: 2026-10-03 Publisher: TradeLabs AI (https://tradelabsai.com). Education, not financial advice. Cite as: TradeLabs Learn, "Open Interest", https://learn.tradelabsai.com/markets/open-interest/ Open interest is the total number of futures or options contracts that are still open, meaning they have been created and not yet closed, exercised or expired. It applies only to derivatives, because every contract has a buyer and a seller and exists until one of them closes it. While volume counts how many contracts traded today, open interest counts how many are outstanding right now. ## Open interest vs volume | | Volume | Open interest | |---|---|---| | Measures | Contracts traded in a period | Contracts outstanding at a point in time | | Resets | Every period | Carries over from day to day | | Shows | Activity | Total commitment in the market | A contract can trade many times without changing open interest, as positions pass from one trader to another. ## How open interest changes Whether a trade changes open interest depends on whether each side is opening or closing a position: | Buyer | Seller | Effect on open interest | |---|---|---| | Opens a new long | Opens a new short | Rises by 1 | | Opens a new long | Closes an existing long | No change (position passed on) | | Closes an existing short | Opens a new short | No change | | Closes an existing short | Closes an existing long | Falls by 1 | **Example: Following open interest** On Monday, a newly listed contract has zero open interest. Trader A buys 10 contracts from Trader B, both opening: open interest is 10. On Tuesday, A sells 4 contracts to Trader C, who is opening: open interest stays 10, now held by B (short 10), A (long 6) and C (long 4). On Wednesday, B buys back 10 from A and C, who are closing: open interest returns to zero. ## Reading open interest with price Traders combine open interest with price direction to judge whether money is flowing into or out of a move: | Price | Open interest | Common interpretation | |---|---|---| | Rising | Rising | New longs entering; trend supported by new money | | Rising | Falling | Shorts covering; rally may be weaker than it looks | | Falling | Rising | New shorts entering; downtrend supported | | Falling | Falling | Longs exiting; decline may be running out of fuel | These are interpretations, not certainties, and they work best alongside volume and price structure. ## Open interest in crypto Crypto traders watch open interest on perpetual futures closely. A rapid rise in open interest combined with high [Funding Rates](https://learn.tradelabsai.com/crypto/funding-rates/) suggests many leveraged positions on one side. When the price moves against them, forced liquidations can cascade, producing sharp spikes. Falling open interest after such a move shows positions were wiped out. See [Liquidations in Crypto](https://learn.tradelabsai.com/crypto/liquidations-in-crypto/) and [Perpetual Futures](https://learn.tradelabsai.com/crypto/perpetual-futures/). ## Open interest in options For options, open interest is reported per strike and expiry. Large open interest at a strike can show where traders are positioned and can influence prices near expiration, as market makers adjust their hedges. Concentrated put open interest is sometimes read as protection demand; concentrated call open interest as speculation or covered call selling. See [Options Open Interest Analysis](https://learn.tradelabsai.com/options/options-open-interest-analysis/) and [Dealer Gamma Exposure](https://learn.tradelabsai.com/options/dealer-gamma-exposure/). ## Where to find it - **Futures exchanges** publish daily volume and open interest for each contract, usually the next morning. - **Option chains** at brokers show open interest per strike, updated daily. - **Crypto data sites and exchanges** show live or frequently updated open interest for perpetuals. - The CFTC's weekly **Commitments of Traders** report breaks down futures open interest by type of trader. ## Liquidity and open interest Contracts with high open interest usually have more liquidity and tighter spreads. Options at strikes with very low open interest can be costly to trade and hard to exit. When choosing between similar contracts, open interest is a useful liquidity check alongside volume. ## Frequently asked questions ### Is high open interest bullish? Not by itself. High open interest means many contracts are open; whether that is bullish or bearish depends on price direction and who holds the positions. ### When is open interest updated? For exchange traded futures and options, it is usually updated once a day after settlement. Many crypto exchanges update it continuously. ### Do stocks have open interest? No. Open interest applies to derivatives such as futures and options, not to shares. ## Sources - Wikipedia, [Open interest](https://en.wikipedia.org/wiki/Open_interest) - U.S. Commodity Futures Trading Commission, [Commitments of Traders](https://www.cftc.gov/MarketReports/CommitmentsofTraders/index.htm) ## Continue learning - Next lesson: [Slippage](https://learn.tradelabsai.com/markets/slippage/) - Previous lesson: [Volume](https://learn.tradelabsai.com/markets/volume/) - Related: [Volume](https://learn.tradelabsai.com/markets/volume/): Volume is the number of shares or contracts traded in a period. Learn how to read volume bars, what high and low volume mean and how volume confirms price moves. - Related: [What Is a Future?](https://learn.tradelabsai.com/markets/what-is-a-future/): A futures contract is an agreement to buy or sell something at a set price on a future date. Learn how futures work, margin, leverage, settlement and who uses them. - Related: [Options Open Interest Analysis](https://learn.tradelabsai.com/options/options-open-interest-analysis/): Open interest counts option contracts still open. Learn how to read open interest with volume, the put call ratio, max pain and unusual activity, and their limits. - Related: [Perpetual Futures](https://learn.tradelabsai.com/crypto/perpetual-futures/): Perpetual futures are crypto derivatives with no expiry, kept close to spot by funding payments. Learn how perps work, leverage, margin, funding and the main risks. - Related: [Liquidations in Crypto](https://learn.tradelabsai.com/crypto/liquidations-in-crypto/): A liquidation is the forced closing of a leveraged crypto position when margin runs out. Learn how liquidation prices work, cascades, heatmaps and how to avoid them.