The formula behind the numbers
For a long call: profit per share = max(0, stock price at expiry − strike) − premium paid. For a long put: profit per share = max(0, strike − stock price at expiry) − premium paid. Multiply by contract size (usually 100 shares) and the number of contracts to get total profit or loss. This options calc works the same way whether you plug in a call option calculator scenario or a put — only which side of the strike pays off flips.
Breakeven, max loss, and max gain
Breakeven is the stock price where the position nets to zero: strike + premium for a call, strike − premium for a put. Max loss on a long option is always capped at the total premium paid — you can never lose more than you put in. Max gain differs by side: a long call option calculator has to leave gain unlimited, since the stock price has no ceiling; a long put caps out when the stock hits $0, so max gain is capped at (strike − premium) × contract size.
Worked example
Buy 1 long call option, strike $100, premium $3.50, contract size 100 shares. If the stock is $108 at expiry: intrinsic value is $8, profit per share is $8 − $3.50 = $4.50, total profit is $4.50 × 100 = $450. Breakeven was $103.50 — anything below that at expiry and the option (and the $350 premium) expires worthless.
What this option profit calc does not do
This is an at-expiry model, not a live options-pricing model — it doesn't account for time value, implied volatility, or early exercise, all of which move an option's price before expiry. For that you'd want a full options-pricing (Black-Scholes) tool; this calculator answers the simpler, more common question: what does this position pay out if held to expiry.
One honest note: Edgelog doesn't journal options trades today — it's a free journal for forex and crypto, with MT4/MT5 auto-sync and read-only Binance/Bybit sync. If that's what you trade alongside options, start free and see the forex journal guide or crypto journal guide for how the sync works.