Stock Profit Calculator
The Math of Trading
Buying low and selling high sounds simple, but in the real world of investing, hidden fees and math errors can eat into your profits. Whether you are day trading stocks, holding crypto, or investing in ETFs, you need to know your exact numbers.
This calculator determines your Net Profit by subtracting your total costs (shares + fees) from your total revenue (sale price - fees).
Why Commissions Matter (The Silent Killer)
While many modern brokerages (like Robinhood or Webull) offer "$0 Commission" trading, fees still exist. They often hide in the "Spread" or in specific fees for options and crypto.
If you trade frequently with fees, your Break-Even Price moves higher.
You buy 10 shares at $10. (Cost $100).
You pay a $5 commission to buy and $5 to sell. (Total Fees $10).
Total Cost Basis = $110.
To break even, the stock price must rise to $11.00 (a 10% gain) just to pay the fees.
Cost Basis vs. Market Value
Your Cost Basis is the total amount of money you put into the trade, including fees. It is the most important number for tax purposes.
- Profit: When you sell for more than your Cost Basis.
- Loss: When you sell for less than your Cost Basis.
Understanding Taxes (Short vs. Long Term)
The profit number you see on the calculator is your "Pre-Tax" profit. The government treats investment income differently depending on how long you held the asset.
1. Short Term Capital Gains
If you sell an asset held for less than a year, the profit is taxed as regular income. This can be as high as 37% depending on your tax bracket.
2. Long Term Capital Gains
If you hold an asset for more than a year, you qualify for a lower tax rate (usually 0%, 15%, or 20%).
| Holding Period | Tax Rate (US) | Strategy |
|---|---|---|
| < 1 Year | Regular Income Tax | Day Trading / Swing Trading |
| > 1 Year | 0% - 20% (Lower) | Investing / "HODLing" |
Crypto Trading vs. Stocks
This calculator works perfectly for Crypto as well. Simply enter the number of "Coins" instead of shares.
However, be aware that Crypto exchanges often charge much higher fees (sometimes up to 2-3% per transaction on credit card buys). Always input these into the "Commission" field to see your true ROI.