Stock Profit Calculator

Use this Stock Calculator to estimate the profit or loss from buying and selling shares. It includes optional buy and sell commissions and calculates total cost, net sale proceeds, ROI, break-even selling price, and profit or loss per share.

Important: This is a trade-return calculator, not a stock-price prediction or valuation tool. Taxes, dividends, market slippage, and investment holding period are not included.

Stock Profit Calculation

First calculate the value of the shares purchased:

Purchase value = number of shares × buy price per share

If a buy commission applies:

Total buy cost = purchase value + buy commission

For the sale:

Sale value = number of shares × sell price per share

Net sale proceeds = sale value − sell commission

The resulting profit or loss is:

Profit or loss = net sale proceeds − total buy cost

Return on Investment (ROI)

The calculator uses a simple trade-level return:

ROI = profit or loss ÷ total buy cost × 100

A positive result represents a gain, while a negative result represents a loss.

Profit or loss per share is:

Per-share result = profit or loss ÷ number of shares

Break-Even Share Price

The break-even price is the selling price needed for net sale proceeds to equal your total buy cost.

With a fixed selling commission:

Break-even price = (total buy cost + sell commission) ÷ number of shares

If the selling commission is percentage-based, the calculator also accounts for that percentage when solving for the required selling price.

Worked Example

Suppose you:

• Buy 100 shares at $20 each
• Pay a $10 buy commission
• Sell the shares at $24 each
• Pay a $10 sell commission

Purchase value:

100 × $20 = $2,000

Total buy cost:

$2,000 + $10 = $2,010

Sale value:

100 × $24 = $2,400

Net sale proceeds:

$2,400 − $10 = $2,390

Profit:

$2,390 − $2,010 = $380

ROI:

$380 ÷ $2,010 × 100 ≈ 18.91%

Profit per share:

$380 ÷ 100 = $3.80

The break-even selling price with the $10 selling commission is:

($2,010 + $10) ÷ 100 = $20.20 per share

Important Notes

• The calculator includes entered transaction commissions when estimating the trade result.
• If you enter commissions as percentages, they are calculated from the corresponding transaction value.
• Brokerage fees, regulatory fees, bid-ask spreads, and market slippage may make actual proceeds different from the estimate.
• Dividends and other distributions are not included, so this is not a total-return calculation.
• Taxes on capital gains or losses are not calculated.
• ROI is a simple percentage return and does not account for how long the investment was held. It should not be interpreted as an annualized return.
• Stock prices can fluctuate significantly, and a calculated potential profit does not predict future investment performance.
• The currency selection is for expressing the entered values consistently; do not mix amounts denominated in different currencies without first converting them.

Sources

• FINRA — Cost Basis Basics
• Investor.gov — Stocks
• Investor.gov — How Fees and Expenses Affect Investment Returns