Strike Price

FundamentalOptions & Derivatives2 min read

Quick Definition

The predetermined price at which the holder of an option can buy (call) or sell (put) the underlying asset upon exercise.

What Is Strike Price?

The strike price (also called exercise price) is the fixed price at which an option contract can be exercised. For call options, the strike is the price at which the holder can buy the underlying; for put options, it is the price at which the holder can sell. Strike prices are set by the options exchange and listed at standardized intervals that depend on the underlying's price level — typically $1 intervals for stocks under $50, $2.50 for stocks $50-$200, and $5 for higher-priced stocks. The relationship between strike price and current stock price determines the option's moneyness (ITM, ATM, OTM), which directly impacts the option's delta, premium composition, and probability of profit. Strike selection is one of the most important decisions in options trading — it determines the trade's risk/reward profile, capital requirement, and probability of success.

Strike Price Example

  • 1AAPL options at $185 have strikes available at $170, $175, $180, $185, $190, $195, $200 — the $185 strike is ATM, $170 is deep ITM (call), $200 is OTM (call)
  • 2A trader chooses the $50 strike for a covered call because it offers a 10% upside from the current $45.50 stock price while providing a $2 premium