Trading term

What is Strike price?

The strike price is the fixed price at which an option lets its holder buy (for a call) or sell (for a put) the underlying asset. It's the reference point that determines whether an option has value — the relationship between the strike and the market price is what makes an option profitable or worthless.

Every option contract is defined by its strike. A $50 call gives the right to buy at $50; a $50 put, the right to sell at $50 — regardless of where the stock actually trades. The strike is chosen when the option is bought, from a ladder of available strikes above and below the current price. It never changes over the life of the contract; what changes is the market price relative to it.

The strike is the hinge of an option's value. For a call, the further the stock rises above the strike, the more the option is worth (it's 'in the money'); below the strike it has no intrinsic value ('out of the money'). Puts are the reverse. Choosing a strike is a core decision: a strike close to the current price costs more premium but needs a smaller move to profit, while a far-away (out-of-the-money) strike is cheap but needs a big move. The strike sets both the cost and the odds.

The strike is the hinge of value
$0 P&LprofitlossStrike = $50break-even $52underlying price at expiry →The strike is the hinge: below it the call is worthless; above it, value grows 1:1

On this $50 call, the strike is where the payoff bends: below it the option has no value; above it, value grows one-for-one with the stock. Every option is defined by its strike.

For example

With a stock at $52, a $50 call is 'in the money' by $2 (you could buy at $50, worth $52). A $55 call on the same stock is 'out of the money' — the $55 strike is above the market, so it has no intrinsic value yet and costs less.

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Why it matters to you

The strike price is the single choice that shapes an option trade's cost, risk, and probability all at once — pick it well and you balance premium against the move you need. Understanding strikes is the gateway to everything in options, because moneyness, breakeven, and every strategy are defined relative to the strike.

Cheap far-out strikes are cheap for a reason

Beginners are drawn to far out-of-the-money strikes because the premium is tiny and the potential percentage return looks huge. But those strikes are cheap because they're unlikely to pay off — the stock has to make a big move fast. Buying deep-OTM strikes repeatedly is a common way to bleed premium on lottery tickets that usually expire worthless.

Frequently asked questions

What is the strike price of an option?

The strike price is the fixed price at which an option's holder can buy (call) or sell (put) the underlying asset. It's set when the option is bought and doesn't change. Whether the stock's market price is above or below the strike determines if the option has value.

How do you choose a strike price?

It's a trade-off. A strike near the current price costs more premium but needs only a small move to profit; a far out-of-the-money strike is cheaper but needs a big move. Traders pick a strike to balance cost against the size and probability of the move they expect.

What does 'in the money' mean for a strike?

A call is in the money when the stock is above the strike (you could buy below market); a put is in the money when the stock is below the strike (you could sell above market). In-the-money options have intrinsic value; out-of-the-money ones don't.

Can the strike price change?

No — the strike is fixed for the life of the contract. What changes is the underlying's market price relative to the strike, which moves the option's value. (Strikes are adjusted only for corporate actions like splits, which mechanically restate the contract.)

Related terms

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