Open Interest(OI)
Open Interest is the total number of outstanding (un-squared-off) option contracts at a strike — a gauge of where positioning is concentrated.
What Open Interest Means
Open Interest (OI) is the total number of option contracts that are currently open — neither exercised, closed, nor expired — at a given strike and expiry. Unlike volume (which counts every trade in a day), OI is a running tally of live positions, so it shows where money is actually parked.
A rising OI means new contracts are being created (fresh positioning); a falling OI means positions are being closed (unwinding). This is why change in OI matters more than the absolute number.
Reading OI for Support and Resistance
The strike with the highest call OI often acts as resistance — writers there do not expect the index to cross that level. The strike with the highest put OI often acts as support. In Nifty, these "max OI" strikes frequently behave like magnets into expiry.
Combine OI with price: rising OI + rising price = fresh longs (bullish conviction); rising OI + falling price = fresh shorts (bearish conviction); falling OI = an existing trend losing fuel. Quintal Mind streams live OI and OI-change across the chain so these shifts are visible as they happen.
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