The meaning of Open Interest • Reading direction from PCR • Bid-Ask spread • Strike selection • Max Pain theory
What Is an Option Chain?
An option chain is a table that lists every available option for a given index or stock — with both CE (Call) and PE (Put) contracts for each strike price. Open the NIFTY option chain and you can see all the 24000 CE, 24100 CE, 24000 PE, 24100 PE contracts in one place.
Beginners often trade on price alone. Experienced traders treat the option chain as a market X-ray — because it reveals where the large operators are positioned.
Open Interest (OI) — The Most Important Column
OI means: the number of contracts that are currently open — that is, the number of traders who have positions and have not yet exited.
Rising OI = new positions being built = conviction in the market
Falling OI = positions being closed = uncertainty
| OI Behaviour | Price | Interpretation |
|---|---|---|
| OI ↑ (rising) | Price ↑ | Bullish — buyers are strong |
| OI ↑ (rising) | Price ↓ | Bearish — sellers are adding positions |
| OI ↓ (falling) | Price ↑ | Short covering — relief rally |
| OI ↓ (falling) | Price ↓ | Long unwinding — bulls exiting |
The strike with the highest OI acts as support or resistance. Large operators defend their positions there. In NIFTY, highest OI on 24000 PE means 24000 is a strong support level.
PCR Ratio — Put Call Ratio
PCR = Total Put OI ÷ Total Call OI
This tells you how much fear exists in the market.
| PCR Value | Meaning | Trading Implication |
|---|---|---|
| PCR > 1.5 | More puts = elevated fear | Contrarian bullish signal |
| PCR 0.8 – 1.2 | Balanced market | Neutral — wait |
| PCR < 0.7 | More calls = greed | Contrarian bearish signal |
Bid-Ask Spread — Liquidity Check
Bid = the price buyers are willing to pay
Ask = the price sellers are asking for
If the NIFTY 24100 CE shows Bid = 85 and Ask = 87, the spread is ₹2. A tight spread means a liquid option — easy to enter and exit.
Deep OTM options often have very wide spreads — ₹20–30. That is an instant ₹20 loss at entry. Avoid these until you are experienced.
Strike Selection — ATM, ITM, OTM
Assume NIFTY is trading at 24,150:
- ATM (At The Money) — 24150 CE/PE — highest liquidity, fast time decay
- ITM (In The Money) — 24000 CE — expensive, lower risk, slower decay
- OTM (Out of Money) — 24300 CE — cheap, high risk, fast decay
Summary — Key Takeaways
- The highest-OI strike acts as strong support or resistance
- PCR > 1.2 = more puts = contrarian bullish signal
- Tight bid-ask spread = good liquidity = safe to trade
- ATM options are the best choice for beginners
- Always combine OI with price action — never rely on one alone
Ready to Trade with Real Capital?
You have learned it — now apply it. Start trading on a ₹5L funded account at Sycnap's Tradez.
Start Challenge Now →