Buying a call gives the right, not the obligation, to buy shares at the strike price. Your loss is limited to the premium, while the profit is theoretically unlimited if the stock rises above the break-even price.
How to use the Call Option Calculator
- Strike price
- Price of the call option (premium)
- Number of option contracts
- Target stock price at expiry
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the strike price, the option premium, the number of contracts and the stock price you expect at expiry.
Tips
- Use annualised volatility and interest rates as decimals per year.
- Remember that one standard option contract usually covers 100 shares.
- Options lose time value as expiry approaches – re-run the numbers as dates change.
- Derivatives can lose more than you expect; understand the maximum loss before trading.
Common mistakes to avoid
- Mixing days and years for time to expiry.
- Ignoring commissions and the bid–ask spread.
- Forgetting dividends when pricing options on dividend-paying stocks.
Inputs explained
| Field | What to enter |
|---|---|
| Strike price | Amount in your currency |
| Price of the call option (premium) | Amount in your currency |
| Number of option contracts | A number |
| Target stock price at expiry | Amount in your currency |
What each result means
- Total call cost (premium) = [Price of the call option (premium)]×100×[Number of option contracts]
- Break-even stock price = [Strike price] + [Price of the call option (premium)]
- Profit or loss at the target price = (max([Target stock price at expiry] – [Strike price], 0) – [Price of the call option (premium)])×100×[Number of option contracts]
- Return on premium = [Profit or loss at the target price]÷[Total call cost (premium)]×100
- Maximum loss = [Total call cost (premium)]
Example values
How the main result changes when Strike price changes and everything else stays at the example values above:
| Strike price | Profit or loss at the target price |
|---|---|
| 75 | 16,500 |
| 112.5 | 9,000 |
| 150 | 1,500 |
| 187.5 | -900 |
| 225 | -900 |
| 300 | -900 |
Formula
Total premium = premium × 100 × contractsBreak-even = strike + premiumProfit at expiry = [max(price − strike, 0) − premium] × 100 × contractsWorked example
Inputs — Strike price: $150; Price of the call option (premium): $4.5; Number of option contracts: 2; Target stock price at expiry: $162.
Results — Total call cost (premium) = $900.00; Break-even stock price = $154.50; Profit or loss at the target price = $1,500.00; Return on premium = 166.67 %; Maximum loss = $900.00.
Frequently asked questions
What is a call option?
The right to buy 100 shares at the strike price before or at expiry.
What is the break-even price?
Strike price plus the premium paid.
What is the most I can lose buying calls?
The premium you paid.
What formula does the Call Option Calculator use?
Total premium = premium × 100 × contracts.