A strike price is the fixed price written into an options contract at which the buyer can exercise their right to buy (for a call) or sell (for a put) the underlying stock. It never changes for the life of that contract, no matter where the stock actually trades.
Every options chain you look at is really just a list of strike prices, above and below the current stock price, each with its own premium.
In, At, and Out of the Money
A strike price's relationship to the current stock price is described with three terms you'll see constantly:
| Term | For a Call | For a Put |
|---|---|---|
| In-the-money (ITM) | Stock price above strike | Stock price below strike |
| At-the-money (ATM) | Stock price ≈ strike | Stock price ≈ strike |
| Out-of-the-money (OTM) | Stock price below strike | Stock price above strike |
ITM options carry intrinsic value (see what is an options contract for the intrinsic/extrinsic breakdown); OTM options are pure time value and become worthless if they're still OTM at expiration.
How Traders Choose a Strike
There's no single "correct" strike — it's a tradeoff along a few dimensions, and ScalpClock doesn't tell you which one to pick. What's useful is understanding what actually changes as you move the strike further from the stock price:
- Cost. Deeper ITM strikes cost more; further OTM strikes cost less.
- Probability. A strike closer to (or past) the current price has a statistically higher chance of finishing in-the-money than one far away — this is closely related to Delta, which is often used as a rough probability estimate.
- Leverage. Further OTM strikes move less in dollar terms per $1 move in the stock, but represent a larger percentage gain if the stock moves enough to reach them — and a total loss if it doesn't.
- Sensitivity to being early. Being right about direction but wrong about timing hurts an OTM position more, since it depends more heavily on getting there before time value decays away.
Choosing a strike is a risk decision, not a formula. Traders with different risk tolerances and different theses about a stock will reasonably choose different strikes on the exact same setup.
A Worked Example
A stock is trading at $80. Here's how three different call strikes on the same stock compare, all else equal:
| Strike | Status | Typical relative cost |
|---|---|---|
| $75 Call | In-the-money | Higher |
| $80 Call | At-the-money | Medium |
| $85 Call | Out-of-the-money | Lower |
If the stock rises to $88 by expiration, all three finish in-the-money — but the $85 call (bought cheapest) shows the largest percentage return, while the $75 call (bought most expensive) shows the smallest percentage return, even though every strike gained the same $8 of intrinsic value per share. This is the leverage tradeoff in action.
Practice Reading Real Options Chains
ScalpCharts shows live price action so you can see how strikes at different distances from the stock actually behave.
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