How to Read a Live Option Chain: OI, IV, LTP & PCR
A plain-English guide to reading a NIFTY option chain — LTP, open interest and OI change, implied volatility, volume and PCR — and what each column actually tells a trader.
The option chain is the single densest screen in options trading, and it scares most beginners off. But you only need to understand a handful of columns to read it like a professional. Here is what each one means and how traders use it.
The columns that matter
- LTP — the last traded price (premium) of that call or put.
- OI (open interest) — the number of contracts currently open at that strike. It is a level, not a flow.
- OI change — how much OI has grown or shrunk versus the previous day's close. This is where the day's fresh positioning shows up.
- Volume — contracts traded today. High volume with little OI change means intraday churn; high volume and rising OI means real positioning.
- IV (implied volatility) — the market's expectation of future movement, priced into that option.
Open interest: where the positions are
The strike with the largest call OI often acts as resistance — a wall of call writers betting price stays below it. The strike with the largest put OI often acts as support. Watching where these walls build (and shift) through the day is one of the most reliable reads in intraday options.
OI change: today's story
The change in OI, combined with the price move, classifies fresh activity into four buildups: Long Buildup (OI up, price up), Short Buildup (OI up, price down — fresh writing), Short Covering (OI down, price up), and Long Unwinding (OI down, price down). This tells you whether a move is being driven by new money or by positions being closed.
PCR: a quick sentiment gauge
The Put-Call Ratio (total put OI ÷ total call OI) is a one-number sentiment gauge. A PCR above 1 means more puts are open than calls (often read as supportive/bullish positioning); below 1 leans the other way. Treat it as context, not a signal on its own.
See it live
The best way to learn the chain is to watch it move. STRYKR's live option chain shows every column above across NIFTY, Bank Nifty, Sensex and MCX, with an OI-by-strike chart, Max Pain, and support/resistance walls computed for you.