Live NSE option chain for POWERGRID (Power Grid Corp. Ltd.), contract size 1,900 shares — strike-wise open interest, change in open interest, implied volatility and last traded price for every listed expiry, with max pain, the OI walls and the expected move computed from the chain.
How to read this option chain
The chain above is NSE's own data, unaltered. What follows is how to get a reading out of it — which columns carry information, which are noise, and what the derived numbers at the top are actually claiming.
Read change in OI, not open interest
The open interest column tells you how many contracts are outstanding at each strike. It is a level, it accumulates over the life of the expiry, and by Wednesday of a weekly contract it mostly tells you what happened on Monday. The column that carries today's information is change in OI.
Read it against what price did, and it resolves into four cases. Price up with OI rising is fresh buying — new longs. Price down with OI rising is fresh selling — new shorts. Price up with OI falling is short covering, which is a rally caused by people leaving rather than arriving, and it stops as abruptly as it started. Price down with OI falling is long unwinding. Those four cover almost everything, and the cheat sheet sets each of them out with the caveats.
What the walls are and aren't
The five strikes carrying the heaviest open interest are numbered in the table. The common description is that these act as support and resistance, which overstates it. What a heavy call strike above spot actually means is that a lot of writers have taken a position that pays if the index stays below it — usually well-capitalised participants, often hedged elsewhere, and under no obligation to defend anything.
Treat them as levels where a large amount of money has an interest, which is a real thing and worth knowing, rather than as a ceiling. They break regularly. When one does, the move through it is frequently faster than the move up to it, because the writers who were short that strike have to do something about it.
The summary numbers, ranked by how much to trust them
The expected move is the most useful and the least discussed. It comes from the at-the-money straddle price, which is roughly what the market charges for the index to move at all before expiry — so it is also, roughly, the move the market is pricing. If your target is outside that range, you are betting against the entire options market's estimate, which is allowed but is worth doing on purpose.
IV rank is next. Implied volatility on its own is a number with no scale; IV rank places it inside its own recent range, which is what turns it into "options are dear today" or "options are cheap today". That single judgement decides whether buying or selling premium is the sensible side of a trade far more often than any directional view does.
PCR and max pain come last. PCR is worth watching as a trend through the session rather than as a level. Max pain identifies the strike at which the most option value expires worthless; it is widely watched, which gives it some self-fulfilling weight into expiry, and there is no mechanism underneath it beyond that.
The buildup bias is our own arithmetic, not NSE's — each near-the-money strike's change in open interest weighted into one bullish or bearish line. It describes positioning that has already happened. It is not a forecast, and the scorecard keeps the record of how it has done.
Before you act on any of it
Option chain data is end-of-poll, not tick-by-tick, and NSE's own figures can lag in a fast move. Open interest is reported with the exchange's own delay. And every reading on this page describes the market's current positioning — which is a description of the past, however recent, and can reverse within minutes of you reading it.