How Options Are Priced

When you look at an options chain and see one call priced at $6.50 while another at a different strike costs $1.20, that difference is not arbitrary. Every options price is the result of six specific inputs interacting through a mathematical pricing model. Understanding these inputs is the single most useful piece of foundational knowledge in options trading because it explains why options behave the way they do in every market condition.

The six inputs that determine options price

The most widely used options pricing model is Black-Scholes, developed in 1973. It takes six inputs and produces a theoretical fair value for any option. Every options price you see on a chain is essentially the market's consensus answer to this calculation.

Input 1: Current stock price

The most obvious input. As the stock price rises, call options become more valuable and put options become less valuable. As it falls, the reverse. The stock price determines how much intrinsic value an option currently has.

Input 2: Strike price

The fixed price at which the option gives you the right to buy or sell. The relationship between the stock price and the strike price determines whether the option is in the money, at the money, or out of the money. Deeper in-the-money options cost more. Further out-of-the-money options cost less.

Input 3: Time to expiration

More time means higher premium. With more days remaining, the stock has more opportunity to make a favorable move, so the option is worth more. As expiration approaches, this time value erodes through theta decay. An option with 90 days remaining is worth more than the same option with 10 days remaining, all else being equal.

Input 4: Implied volatility

The most influential input after the stock price itself. Implied volatility reflects the market's expectation of how much the stock will move. Higher implied volatility means more expensive options across all strikes and expirations. When a stock's IV spikes before earnings, option prices rise dramatically. When IV collapses after the event, prices fall. IV is the input that changes most frequently and creates the most opportunity for options traders.

Input 5: Risk-free interest rate

Higher interest rates increase the value of calls slightly and decrease the value of puts slightly. This effect is small for short-dated options and more meaningful for long-dated options like LEAPS. The Greek that measures this sensitivity is rho.

Input 6: Dividends

Expected dividends reduce call values and increase put values. When a stock pays a dividend, the share price typically drops by the dividend amount on the ex-dividend date, which reduces the value of calls. Traders holding short calls on dividend-paying stocks need to be aware of this dynamic.

The two components of any option price

Every option price is made up of two parts that together equal the total premium:

Intrinsic value: the real, immediate value of the option if exercised right now. Only in-the-money options have intrinsic value. For a call, intrinsic value equals the stock price minus the strike price (when positive). For a put, it equals the strike price minus the stock price (when positive).

Example: AAPL at $195. The $185 call has $10 of intrinsic value. The $200 call has zero intrinsic value.

Extrinsic value: everything above intrinsic value. Also called time value. This is the premium the market charges for the possibility that the option could become more valuable before expiration. Extrinsic value is driven by time remaining and implied volatility. All options have extrinsic value until expiration. Out-of-the-money options are entirely extrinsic value.

Total premium = intrinsic value + extrinsic value

At expiration, extrinsic value reaches zero. An option at expiration is worth exactly its intrinsic value (if in the money) or zero (if out of the money).

Why the same stock can have very different option prices at different times

Option prices on the same stock at the same strike can differ dramatically depending on the timing. A 30-day AAPL $190 call might cost $3.00 in a calm market but $6.00 the week before earnings.

The stock price and strike are the same. The difference is implied volatility. In the week before earnings, IV spikes as the market prices in the uncertainty of the announcement. This IV inflation doubles the extrinsic value of every option on the chain.

This is why checking implied volatility and IV rank before every options trade is essential. You might be buying or selling the same contract at very different prices depending purely on where IV sits.

How the inputs translate to strategy decisions

High implied volatility: options are expensive. Sellers collect more premium. Buyers pay more for the same exposure. Selling strategies (iron condors, covered calls, credit spreads) have a better risk-reward in high IV environments.

Low implied volatility: options are cheap. Buyers get better value. Sellers collect less premium. Buying strategies (long calls, debit spreads, LEAPS) make more sense when IV is depressed.

More time to expiration: higher premium, slower theta decay. Better for buyers who want time for their trade to work. More expensive for sellers but they collect more.

Less time to expiration: lower premium, faster theta decay. Better for sellers who want rapid time value erosion. Riskier for buyers who need the stock to move quickly.

Related terms: Implied volatility, IV rank, intrinsic value, extrinsic value, theta, vega, Black-Scholes, premium

Try it on Stryke: Compare option prices across different strikes, expirations, and IV levels in the Options Screener to see these pricing inputs in action.

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