The option chain is the single most useful screen for anyone trading NIFTY options. It shows every strike price for one expiry, with the call options on the left and the put options on the right, and live numbers for each.

At first it looks like a wall of numbers. Once you know what each column means, it becomes a map of where traders are positioned. This guide walks through it column by column.

The layout: calls on the left, puts on the right

The middle column lists strike prices, usually in steps of 50 points for NIFTY. Every row is one strike. The left half of the row is the call option (CE) for that strike, and the right half is the put option (PE).

The row closest to the current NIFTY price is the at-the-money (ATM) strike. Strikes below the spot price are in-the-money for calls and out-of-the-money for puts. Strikes above the spot are the opposite.

  • ATM (at the money): the strike nearest to the current NIFTY price.
  • ITM (in the money): an option that already has intrinsic value.
  • OTM (out of the money): an option with only time value; it is cheaper and decays faster.

The columns that matter most

Different platforms show slightly different columns, but these are the ones traders look at every day.

  • LTP (last traded price): the latest premium of that option.
  • OI (open interest): how many contracts are still open at that strike. Big OI means a lot of positions are sitting there.
  • Change in OI: how much OI was added or removed today. This shows fresh positioning, not old positions.
  • Volume: how many contracts traded today. High volume with little change in OI often means intraday traders entering and exiting.
  • IV (implied volatility): how expensive the option is relative to the expected movement. Rising IV makes premiums costlier.

Reading support and resistance from OI

Option writers (sellers) are often large, well-capitalised participants, so traders watch where they build positions. A strike with very large call OI is often treated as a resistance zone, because call writers there expect NIFTY to stay below it. A strike with very large put OI is often treated as a support zone, for the opposite reason.

These levels are not walls. They shift during the day as writers add, cut or roll positions. That is why change in OI matters more than total OI for intraday reading: it tells you where new positions are being built right now.

A simple routine to read it in two minutes

Many traders follow the same short routine every morning and during the day:

  • Find the ATM strike and look 4–5 strikes above and below it.
  • Note the strike with the highest call OI above the spot and the highest put OI below it.
  • Check change in OI: which side is adding faster today, calls or puts?
  • Look at PCR (put-call ratio) for the overall tilt of positions.
  • Re-check every 15–30 minutes, because positioning changes through the session.

Common mistakes

  • Treating the highest OI strike as a guaranteed top or bottom. It is a zone of interest, not a promise.
  • Looking at total OI only and ignoring today's change in OI.
  • Reading the chain of a far expiry when trading the current week; positioning is very different across expiries.
  • Ignoring IV. A cheap-looking option can still be expensive if IV is high.