Introduction
This free options calculator helps you find the fair price of a call or put option using proven math models. Enter a stock price, strike price, expiration date, and implied volatility, and the tool does the rest. It gives you the theoretical option price, the Greeks (like delta, gamma, theta, vega, and rho), and a clear breakdown of intrinsic and time value.
You can price both European options with the Black-Scholes-Merton model and American options with a binomial tree model. The calculator also supports dividend-paying stocks, lets you reverse-solve implied volatility from a market premium, and shows how the option price changes as the underlying moves.
Need to analyze a full strategy? Open the multi-leg builder to set up spreads, straddles, iron condors, and other combinations. It will show you the net premium, max profit, max loss, breakeven prices, and a payoff chart at expiration — all in seconds. For a quicker look at potential gains on a single trade, try our Options Profit Calculator.
Whether you are learning how options work or planning a real trade, this calculator gives you the numbers you need to make a smart decision.
How to Use Our Options Calculator
Enter details about a stock option to get its fair price, Greeks, and profit estimates. The calculator returns theoretical call and put prices, a Greeks breakdown, volatility sensitivity data, and a payoff chart.
Single Option Pricing
Option Style: Choose "European" if the option can only be used on the expiration date. Choose "American" if it can be used at any time before expiration. Most U.S. stock options are American.
Option Type: Pick "Call" if the option gives the right to buy the stock. Pick "Put" if it gives the right to sell the stock.
Underlying Symbol: Type the stock ticker, like AAPL or MSFT, then press the search button to auto-fill the current price.
Current Underlying Price: Enter the current market price of the stock in dollars. This fills in automatically if you use the symbol search. If you want to estimate gains on a stock position itself, see our Stock Profit Calculator.
Strike Price: Enter the price at which the option lets you buy or sell the stock.
Expiration Type: Select weekly, monthly, quarterly, or LEAPS to label your option. This is just a label and does not change the math.
Expiration Date: Pick the date the option expires. This auto-updates the "Days to Expiration" field.
Days to Expiration: Enter the number of days left until the option expires. This auto-updates the expiration date field.
Implied Volatility (%): Enter the expected yearly volatility of the stock as a percent. A higher number means the market expects bigger price swings. Volatility is closely related to standard deviation, which measures the spread of returns around an average.
Premium / Option Price: Enter the current market price of the option. When linked to implied volatility, changing one will update the other.
Risk-Free Rate (%): Enter the annual interest rate on a safe investment like a U.S. Treasury bond. This is used in the pricing model. You can explore how bond rates work with our Bond Yield Calculator.
Dividend Yield (%): Enter the stock's annual dividend yield as a percent. Set this to 0 if the stock does not pay dividends. A value above 0 turns on the dividend-adjusted model. Use our Dividend Yield Calculator to find the yield for any stock.
Units per Lot / Contract Size: Enter how many shares one option contract controls. In the U.S., this is usually 100.
Quantity: Enter how many contracts you are trading. Use a positive number for a long position (buying) and a negative number for a short position (selling).
Link Implied Volatility ↔ Premium: Turn this on to keep IV and premium in sync. When you change one, the calculator solves for the other. Turn it off to enter both values by hand.
Press Calculate to see results. Press Reset to return all fields to their default values. Use Switch to Advanced Mode to see all five Greeks, the volatility sensitivity table, and model details.
Multi-Leg Strategy Builder
Open the Build a Multi-Leg Strategy section to combine up to six option legs into one trade, such as a spread, straddle, or iron condor.
Underlying Symbol: Enter the stock ticker for the strategy.
Current Underlying Price: Enter the current price of the stock.
Trade Date: Pick the date you plan to enter the trade.
Expiration Date: Pick the shared expiration date for all legs, unless you override it on a specific leg.
Lot / Contract Size: Enter the number of shares per contract, usually 100.
Currency: Choose USD, EUR, or GBP to set the display currency.
Legs Table: For each leg, choose call or put, enter the strike price, the premium paid or received, and the quantity. Use a positive quantity for long and a negative quantity for short. Use the expiration override column if a leg expires on a different date.
Click Add Leg to add a new row. The calculator auto-detects common strategies like bull call spreads, strangles, and iron condors. It then shows the net premium, max profit, max loss, breakeven prices, net delta, net theta, and a payoff chart.
What Is an Options Calculator?
An options calculator helps you find the fair price of a stock option before you buy or sell it. A stock option is a contract that gives you the right to buy or sell a stock at a set price by a certain date. The set price is called the strike price, and the date is the expiration date. You pay a fee called a premium to hold this right.
There are two main types of options. A call option gives you the right to buy a stock. A put option gives you the right to sell a stock. Traders use calls when they think a stock price will go up and puts when they think it will go down. To estimate profit or loss on a specific trade, pair this tool with our Options Profit Calculator.
How This Calculator Works
This tool uses proven math models to price options. For European-style options, it uses the Black-Scholes-Merton model, which relies on the normal distribution to estimate the probability of different price outcomes. For American-style options, which can be used before the expiration date, it uses a binomial tree model. You enter the stock price, strike price, days until expiration, implied volatility, and the risk-free interest rate. The calculator then gives you a fair price for both calls and puts.
What Are the Options Greeks?
The calculator also shows values called the Greeks. These tell you how sensitive an option's price is to changes in the market. Delta shows how much the option price moves when the stock moves by $1. Gamma measures how fast Delta itself changes. Theta shows how much value the option loses each day as time passes. Vega shows how the price reacts to changes in volatility. Rho tracks the effect of interest rate changes. Understanding these sensitivities can also help when you use a Position Size Calculator to manage risk across your portfolio.
Multi-Leg Option Strategies
The strategy builder lets you combine up to six options into one trade. Common strategies include bull call spreads, bear put spreads, straddles, strangles, and iron condors. The tool detects your strategy by name, calculates your max profit, max loss, and breakeven prices, and draws a payoff chart so you can see your risk and reward at a glance. For a deeper look at when a business or trade turns profitable, our Break Even Calculator can also be helpful.
Key Terms to Know
- Implied Volatility (IV) — A measure of how much the market expects a stock price to move. Higher IV means higher option prices.
- Intrinsic Value — The real, built-in value of an option if you used it right now.
- Time Value — The extra amount you pay above intrinsic value for the time left until expiration.
- Moneyness — Describes whether an option has intrinsic value. ITM (in the money) means it does. OTM (out of the money) means it does not. ATM (at the money) means the stock price is very close to the strike price.
- Dividend Yield — The yearly dividend a stock pays, shown as a percent. This affects option pricing because dividends lower the stock price on the payment date. You can project future dividend income with our Dividend Calculator.