How to find support and resistance in an option chain

A put writer at 24,500 keeps the full premium only if NIFTY stays above 24,500. If lakhs of contracts are written there, many large traders are betting on that floor and will often hedge or add as price approaches it. The same logic makes heavy call OI a ceiling.

Find the put strike with the highest OI below the spot price; that is support. Find the call strike with the highest OI above spot; that is resistance. Then repeat with OI change and volume. When all three point to the same strike the level is well backed; when they disagree, the OI change level usually matters more intraday.

Look at the next biggest strike on the same side. If it is below about 75% of the top value, or above 75% but falling, the level is strong. If a higher strike is above 75% and rising, the level is shifting towards the top (STT), a bullish sign. If a lower strike is above 75% and rising, it is shifting towards the bottom (STB), a bearish sign.

After the shift completes, the new level is not settled yet. AOC labels these SFT (shifted from top, the level moved lower) in red and SFB (shifted from bottom, the level moved higher) in green, with the time of the shift.

Writers roll positions as the market moves. On a rising day you will see fresh put writing at higher strikes and call writers cutting positions at the strike just above price. Support climbs first, then resistance gives way. On a falling day it runs the other way. Watching these shifts is more useful than any single snapshot of the chain.

AOC computes the resistance (R) and support (S) in the chain header, draws them on the split chart, labels every intraday shift with its time, and keeps a full list in Intraday S/R Shiftings. Tap any strike to see its own support, resistance and reversal prices.