Commissions and fees reduce returns, especially on small trades. Knowing your break-even price helps you set realistic sell targets.
How to use the Stock Calculator
- Number of shares
- Buying price per share
- Buying commission type
- Buying commission
- Selling price per share
- Selling commission type
- Selling commission
- Tax on the gain
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the number of shares, the buying and selling prices and commissions.
Tips
- Take figures from the same financial statements and the same fiscal year.
- Compare ratios with companies in the same industry, not across industries.
- Use several valuation measures together; no single ratio tells the whole story.
- Market prices change every second – refresh the share price before you rely on a result.
Common mistakes to avoid
- Mixing per-share figures with company totals.
- Using trailing earnings for one company and forward earnings for another.
- Forgetting dilution from options and convertible securities.
Inputs explained
| Field | What to enter |
|---|---|
| Number of shares | A number |
| Buying price per share | Amount in your currency |
| Buying commission type | Choose one: Fixed amount, Percentage |
| Buying commission | A number |
| Selling price per share | Amount in your currency |
| Selling commission type | Choose one: Fixed amount, Percentage |
| Selling commission | A number |
| Tax on the gain | In % |
What each result means
- Profit = [Net selling price] – [Net buying price]
- Return on investment (ROI) = [Profit]÷[Net buying price]×100
Example values
How the main result changes when Number of shares changes and everything else stays at the example values above:
| Number of shares | Profit |
|---|---|
| 50 | 390 |
| 75 | 590 |
| 100 | 790 |
| 125 | 990 |
| 150 | 1,190 |
| 200 | 1,590 |
Formula
Net buying cost = shares × buy price + buy commissionNet selling proceeds = shares × sell price − sell commissionProfit = proceeds − cost; ROI = profit ÷ costBreak-even price = (cost + sell commission) ÷ sharesWorked example
Inputs — Number of shares: 100; Buying price per share: $40; Buying commission type: Fixed amount; Buying commission: 5; Selling price per share: $48; Selling commission type: Fixed amount; Selling commission: 5; Tax on the gain: 0 %.
Results — Net buying price = $4,005.00; Net selling price = $4,795.00; Profit = $790.00; Return on investment (ROI) = 19.73 %; Break-even selling price = $40.10; Profit after tax = $790.00.
Frequently asked questions
How do I calculate stock profit?
(Sell price × shares − sell fees) − (buy price × shares + buy fees).
What is the break-even price?
The selling price that exactly covers your cost and commissions.
Are stock profits taxed?
Usually, as capital gains when you sell.
What formula does the Stock Calculator use?
Net buying cost = shares × buy price + buy commission.