Put option profit formula
At expiration, a long put is worth max(0, strike - stock price) per share. Multiply that by 100 shares per standard contract and by the number of contracts, then subtract the premium paid (premium × 100 × contracts). The result is the profit or loss at expiration, before commissions and fees.
The premium input is per share, as equity option prices are quoted. The put side is preset here; the combined options profit calculator switches between calls and puts.
- Put value at expiration = max(0, strike - price) × 100 × contracts.
- Profit or loss = put value - premium × 100 × contracts.
- Break-even at expiration = strike - premium.
- Maximum loss = premium × 100 × contracts.
Worked example: put profit at expiration
Take one put contract with a $100.00 strike, bought for $2.50 per share, and a stock price of $90.00 at expiration. Each line shows the formula, then the numbers, then the result. The calculator above opens with these inputs and displays the same results.
At or above $100.00 at expiration, the put expires worthless and the loss is the full $250.00 premium. Below $97.50, the expiration payoff is larger than the premium paid.
- Break-even = strike - premium = $100.00 - $2.50 = $97.50
- Maximum loss = premium × 100 × contracts = $2.50 × 100 × 1 = $250.00
- Put value at $90.00 = max(0, strike - price) × 100 × contracts = max(0, $100.00 - $90.00) × 100 × 1 = $1,000.00
- Profit or loss at $90.00 = put value - maximum loss = $1,000.00 - $250.00 = $750.00
What this calculator leaves out
The payoff is calculated at expiration. Before expiration, a put also carries time value, which depends on implied volatility, time remaining, interest rates and dividends, so a position closed early can show a different gain or loss than this model at the same stock price.
It covers a long put only: bought, not sold. Short options and spreads have different maximum-loss, margin and assignment rules. Commissions, fees, slippage and nonstandard contract multipliers are excluded. The calculator checks arithmetic; it does not estimate how likely a price is or recommend a trade.