Strike Price
The strike price is the fixed price at which an option can be exercised — the reference level that determines whether an option has intrinsic value and how it behaves.
In one line: The strike price is the fixed price at which an option can be exercised — the reference level that determines whether an option has intrinsic value and how it behaves.
In simple words
The strike is the price locked into the option contract. A call lets you buy at the strike; a put lets you sell at the strike. Choosing the strike is one of the most important decisions in options trading because it sets your cost, your probability of profit and your payoff. Strikes are listed at fixed intervals — every 50 points on Nifty, every 100 on Bank Nifty.
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Strike Price
The strike (20,000) is the hinge of the payoff: the option gains intrinsic value only once the underlying moves past it in the right direction.
Strikes and moneyness
The relationship between the strike and the current price defines moneyness. For a call: strike below spot is in-the-money (ITM), near spot is at-the-money (ATM), above spot is out-of-the-money (OTM). For a put it is reversed. Moneyness drives everything — an ITM option is expensive and behaves like the underlying, while an OTM option is cheap, all time value, and needs a move to pay off. The strike you choose places you somewhere on this spectrum.
Strike intervals on Indian indices
The NSE lists strikes at standard intervals: 50 points apart on Nifty and 100 points apart on Bank Nifty, with more strikes clustered around the current price. This gives traders a fine grid to target specific views. Near-the-money strikes are the most liquid, with the tightest bid-ask spreads and the highest open interest — important for entering and exiting cleanly.
How strike choice shapes a trade
Choosing a higher call strike lowers the premium but reduces the probability of profit and demands a bigger move. A lower, in-the-money strike costs more but has a higher chance of finishing profitable and a higher Delta. There is no universally 'best' strike — it depends on your conviction, your view on how far and how fast the underlying will move, and your risk tolerance. Selling strategies flip the logic: sellers pick strikes far enough away to have a high probability of expiring worthless.
Strikes in multi-leg strategies
In spreads and complex strategies, the gap between strikes defines the risk and reward. A Bull Call Spread's maximum profit is the distance between its two strikes minus the net premium. An Iron Condor's width between short and long strikes sets its maximum loss. Understanding how strike selection interacts across legs is the difference between a well-shaped position and an accidental one.
Practical example (Nifty)
Illustrative — Nifty, lot size 75
Nifty at 20,000. You can buy the 19,900 CE (ITM) for ₹250, the 20,000 CE (ATM) for ₹190, or the 20,300 CE (OTM) for ₹80. The 19,900 call is expensive but already has 100 points of intrinsic value and a high Delta. The 20,300 call is cheap but needs Nifty above 20,380 just to break even. Same view, three very different risk-reward profiles — all decided by the strike.
Why it matters in practice
- The strike sets your moneyness, cost, probability of profit and payoff shape.
- Near-the-money strikes are the most liquid, with tighter spreads and higher open interest.
- OTM strikes are cheaper but need a larger move; ITM strikes cost more but behave like the underlying.
- In spreads, the distance between strikes defines maximum profit and loss.
Common mistakes
- Always buying the cheapest far-OTM strike and wondering why most trades expire worthless.
- Ignoring liquidity and trading illiquid deep-OTM strikes with wide bid-ask spreads.
- Not matching strike distance to a realistic view of how far the underlying can move by expiry.
- In spreads, choosing strike widths without checking the resulting risk-reward and margin.
What professionals do
Experienced traders select strikes by Delta and probability rather than by rupee price — a 0.30-Delta strike means the same thing regardless of the index level. They favour liquid near-the-money strikes for clean fills, size strike distance to a realistic expected move (often guided by the option's implied volatility), and in multi-leg trades they deliberately set strike widths to control risk, reward and margin.
Key takeaway
The strike price is the hinge of every option: it sets moneyness, cost, probability and payoff. Choose strikes by probability and a realistic expected move, favour liquid near-the-money strikes, and in spreads let the strike width define your risk and reward.
Frequently Asked Questions
What is a strike price in options?
How do I choose the right strike price?
What are strike intervals on Nifty and Bank Nifty?
What is the difference between strike price and premium?
What does at-the-money strike mean?
Which strike is best for beginners?
Does the strike price change during the contract?
How does strike width affect a spread?
Why are some strikes more liquid than others?
Sources & references
Educational content only — not investment advice.