There is a moment in every financial decision where you stop reading and start calculating. Payoff at expiry for a bought or written call or put, with the break-even price. This guide is written for that moment. Plain language, one worked example, and a calculator you can open in the next line if you would rather skip straight to your own figures.
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Prefer to start with your own figures? Use the Option Profit & Loss Calculator now, or continue for the formula and a worked example.
How the calculation actually works
At expiry a call is worth whatever the underlying is above the strike, and a put whatever it is below. The buyer's result is that intrinsic value minus the premium paid; the writer's result is the premium received minus the intrinsic value.
The formula behind it:
Call payoff = max(Spot − Strike, 0) − Premium · Put payoff = max(Strike − Spot, 0) − Premium
| Symbol | What it means |
|---|---|
Strike |
Strike price of the option |
Premium |
Price per unit paid or received |
Spot |
Price of the underlying at expiry |
Quantity |
Lots × lot size |
Nothing is rounded away quietly and nothing is assumed on your behalf. If a figure appears in the result, it came from something you entered.
Let us run one real set of numbers
A 24,500 call bought at ₹120 with a 75 lot size breaks even at 24,620 and gains ₹13,500 if expiry is 24,800.
Change any one input and watch the result move — that sensitivity is the real lesson. It is far more useful than memorising a single outcome, because your own rate, tenure or contribution will never match the example exactly.
Using the Option Profit & Loss Calculator, step by step
- Open the Option Profit & Loss Calculator.
- Enter your figures. Use the ones on your statement, sanction letter or scheme document rather than a remembered number.
- Read the result card — the headline figure plus the breakdown that produced it.
- Adjust one input at a time to see what genuinely moves the outcome.
- Tap Download PDF to keep a copy of the calculation, with your inputs and assumptions printed on it.
The PDF takes a few seconds to build because it is a properly typeset report, not a screenshot. You will see a progress message while it is being prepared, and the download starts on its own.
Small habits that make a real difference
- Break-even is the strike plus the premium for a call, and minus it for a put.
- Before expiry the option also carries time value, so the live price will differ from this payoff.
The errors that cost the most
- Forgetting that a bought option can expire worthless and lose the entire premium.
- Writing options without accounting for the margin blocked and the open-ended loss.
If you want to go a level deeper afterwards, read up on option greeks and expiry cycles. Both come up the moment you start comparing options seriously.