Strike Price
The fixed price at which an option's buyer can buy (call) or sell (put) the underlying.
Every listed option is defined by three things: the underlying, the expiry, and the strike price. NIFTY options list strikes in steps of 50 points, BANKNIFTY in steps of 100, FINNIFTY in steps of 50. The exchange sets the step, not the trader.
Where spot sits relative to a given strike is what determines that option's moneyness: at, in, or out of the money.
Example: with NIFTY at 24,970, the listed strikes nearby are 24,900, 24,950, 25,000 and 25,050, each 50 points apart. A BANKNIFTY chain with spot at 51,230 instead lists 51,100, 51,200 and 51,300, a wider 100-point step for a pricier, more volatile index.
Related terms
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