Use this calculator to estimate profit/loss for a single call or put option position at expiration.
What this option trading calculator helps you do
Options can feel complicated because every position has multiple moving parts: strike price, premium, contract size, and where the stock finishes at expiration. This calculator simplifies that process by showing your estimated payoff for a single-leg option trade at expiration.
It supports both calls and puts, and both long and short positions. With just a few inputs, you can quickly evaluate:
- Your estimated total profit or loss
- Break-even price
- Maximum possible profit and maximum possible loss
- A quick scenario table at different stock prices
Inputs explained
1) Option type: call or put
A call gives the holder the right to buy shares at the strike price. A put gives the holder the right to sell shares at the strike price.
2) Position: long or short
Long means you bought the option and paid a premium. Short means you sold the option and received a premium.
3) Strike price
The strike is the price used to determine intrinsic value at expiration. It is the reference point for whether an option is in-the-money or out-of-the-money.
4) Premium per share
Option premiums are quoted on a per-share basis. Most US equity option contracts represent 100 shares, so a premium of $2.50 usually means $250 per contract.
5) Stock price at expiration
This is the key driver of the expiration payoff. The calculator computes intrinsic value and net profit/loss from this price.
6) Number of contracts and multiplier
Contracts let you scale position size. The multiplier is normally 100, but some products use different multipliers.
How the payoff logic works
Call option intrinsic value
Intrinsic value per share = max(Stock Price at Expiry − Strike, 0)
Put option intrinsic value
Intrinsic value per share = max(Strike − Stock Price at Expiry, 0)
Net profit/loss at expiration
- Long option: Intrinsic Value − Premium
- Short option: Premium − Intrinsic Value
Total P/L = Net P/L per share × Contracts × Multiplier
Practical interpretation tips
- Break-even is not a guarantee. It is just the stock price where expiration P/L equals zero.
- Short calls can have unlimited risk. If the stock rallies hard, losses can keep growing.
- Long options lose time value. This calculator focuses on expiration payoff, not mid-trade option pricing.
- Commissions and slippage matter. Real-world results may be lower than modeled estimates.
Example workflow before entering a trade
Suppose you are considering buying 2 call contracts with a $100 strike for a $4 premium. Enter those values, then test multiple expiration prices (for example $95, $100, $105, $115). You can quickly see how sensitive your result is to the underlying move and whether the potential reward justifies the risk.
Final reminder
This tool is for educational planning and trade scenario analysis. It does not model implied volatility shifts, early assignment risk, margin requirements, or Greeks such as delta and theta. Use it as a clear first-pass calculator, then combine it with broader risk management and position sizing rules.