--- title: "Volume or open interest: which matters | RupeeCase" description: "Volume counts the contracts traded during a session, and open interest counts the contracts still open at the close." source_url: "https://www.rupeecase.com/learn/questions/volume-or-open-interest" --- On the 30 Jun 2026 chain, traded volume bunches at a few round strikes and thins out between them Calls and puts together, traded volume in contracts at each strike step around the at the money strike, for the 30 Jun 2026 expiry, 10 Jun 2026. Open interest is charted on the open interest page, in units. Source: NSE end of day data, computed by RupeeCase. As of 10 Jun 2026. Volume and open interest are both counts on an option chain, but they measure different things. Volume is the number of contracts that changed hands in the session. Open interest is the number of contracts still open at the close, meaning positions that have neither been closed out nor expired. A trade can add to volume without changing open interest. When an existing holder sells to a new buyer, the contract trades, but no new position opens. A strike can therefore show heavy volume on a day when its open interest barely moves, and the reverse happens when positions are carried over without much trading. The units differ, and this is where most mistakes start. NSE publishes open interest in units and volume in contracts. One Nifty contract is 65 units, so open interest has to be divided by 65 before it sits beside volume. Compare the two only after both are in contracts. The chart shows volume on the 30 Jun 2026 Nifty chain as it stood on 10 Jun 2026. Trading bunches at a few round strikes near the money and thins out between them. Across the whole chain, the strike with the most open interest sat well above the money, away from the busiest strike. Volume follows where the day's trading happened, and open interest follows where positions have built up, so the two maps can disagree. Use volume to judge how active a strike was and whether a price move had trading behind it. Use open interest to judge how many positions carry into the next session. The [build up patterns](/learn/questions/long-short-build-up) show how open interest and price work together, and the [open interest page](/learn/questions/what-is-open-interest) sets out the units. **Before you trade.** Derivatives trading carries a high risk of loss. SEBI's study "Profitability of Individual Traders in the Equity Derivatives Segment (FY25 to FY26)" (August 2026) found that 87.7% of individual traders in equity F&O made net losses in FY26, with aggregate net losses of Rs 91,685 crore. [Read the SEBI study](https://www.sebi.gov.in/reports-and-statistics/research/aug-2026/study-profitability-of-individual-traders-in-the-equity-derivatives-segment-fy25-fy26-_103835.html) Volume or open interest: which matters?Volume counts the contracts traded during a session, and open interest counts the contracts still open at the close. Volume shows how busy a strike was that day, and open interest shows how many positions carry into the next session, so the two answer different questions. LGo deeper ## Where Learn teaches this. [Go deeperOpen interest, volume and the four build up patterns7 min, Beginner](/learn/path-13/module-13-3-open-interest-and-build-ups)[Go deeperLiquidity in the chain: spreads, volume and tradable strikes9 min, Intermediate](/learn/path-15/module-15-5-option-chain-liquidity) SSources ## Go to the source. 3 sources, NSE the most cited The publisher of each source listed below. Source: Module undefined source list. 1. [NSE, option chain page (the live screen; Learn uses only dated end of day files)](https://www.nseindia.com/option-chain) NSE 2. [NSE, equity derivatives contract specifications (expiry cycle, lot size, settlement)](https://www.nseindia.com/static/products-services/equity-derivatives-contract-specifications) NSE 3. [NISM, Series VIII equity derivatives test objectives (the syllabus names the Greeks, open interest, volume and the put call ratio)](https://www.nism.ac.in/revamp-nism/test-objectives-revised-nism-series-viii-equity-derivatives-certification-examination/) NISM ?Questions people ask ## Related questions. [QuestionWhat are open interest, change in OI and cumulative OI?Beginner](/learn/questions/what-is-open-interest)[QuestionLong build-up, short build-up, short covering, long unwinding?Beginner](/learn/questions/long-short-build-up)[QuestionWhat should I look at in option chain analysis for intraday?Intermediate, trap check](/learn/questions/option-chain-analysis-intraday)[QuestionWhat is PCR and how do I read it?Beginner, trap check](/learn/questions/what-is-pcr)[QuestionWhat do participant wise OI, the FII long short ratio and FII and DII data tell me?Intermediate, trap check](/learn/questions/participant-wise-oi-fii-data) [All 130 questions](/learn/questions/) Explore next ## Go deeper on this question. * [QuestionWhere do I get historical option chain and F&O data in India?A short answer with a dated chart](/learn/questions/historical-option-chain-data) * [QuestionDoes the ATM straddle price tell me the expected move?A short answer with a dated chart](/learn/questions/atm-straddle-expected-move) * [ToolOption payoff builderLegs on a dated Nifty chain, breakevens and charges](/learn/tools/payoff-builder) * [GlossaryInvesting glossary, 230 termsPlain word definitions, and the app’s own](/learn/glossary) Community ## Join my WhatsApp group. Scan the code, fillFill one short form, and join my WhatsApp group. Slides, sources, factsheets and the rebalance logs live there, and members join a daily Google Meet with me. New to RupeeCase? [Getting started](/getting-started) [See the terminal](/terminal) [Sign up for RupeeCase](https://invest.rupeecase.com/signup) [Join the WhatsApp group](https://forms.gle/C6HMtM1Z2GfeocQV7) [One form, one group](https://forms.gle/C6HMtM1Z2GfeocQV7)Scan with your phone camera Education only, not investment advice, a research report or a recommendation to buy, sell or hold any security. RupeeCase (QC Alpha Technologies Pvt Ltd) is not registered with SEBI as an investment adviser or research analyst. Contracts and prices shown are for illustration only, come from NSE end of day files at least 30 days old, and are not recommendatory. Derivatives trading carries a high risk of loss.