Open interest is heaviest at a few round strikes on this chain
Open interest counts positions that are still open, and it is not the same as volume. Volume counts the trades done in the session, and a day can have large volume with almost no change in open interest. Open interest rises when two parties open new positions against each other, and it falls when two holders close against each other.
When one holder hands a position to another, open interest does not change. A transfer of an existing contract leaves the count alone.
Change in OI is the difference from the previous close. A rise in OI with a rising price is usually called a long build up, and a rise in OI with a falling price a short build up. Every contract has a buyer and a seller, so the label names the price move that came with the new contracts, not who is right. The question on long and short build up walks through the four patterns.
Cumulative OI is the total across the strikes of one chain, or across the expiries of one underlying. It describes how much is open, not who holds which side. Divide the units by 65 to get contracts on the Nifty lot.
The chart reads the 30 Jun 2026 Nifty chain as it stood on 10 Jun 2026. Large open interest at a strike shows where many contracts are open. It does not make that strike a wall the index has to respect, and the question on highest OI strikes tests that claim.
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