股票盈亏计算器
计算股票交易的净利润或亏损。输入买入价、卖出价、股数、佣金费用和资本利得税率，即时查看总回报、ROI 和盈亏平衡价格。
Stock Profit Calculator
Calculate your stock trading profits including commissions and capital gains tax
Frequently Asked Questions
股票利润计算器是如何工作的？
股票利润 = (卖出价 - 买入价) × 股数 - 总手续费。利润率 = 利润 / 总投入成本 × 100%。本计算器同时支持计算含手续费的实际净利润和不含手续费的毛利润，并显示投资回报率（ROI）。
如何计算股票投资的年化回报率？
年化回报率（CAGR）= [(期末价值 / 期初价值)^(1/投资年数) - 1] × 100%。例如，投入 $10,000，3 年后变成 $14,400：年化回报率 = (14,400/10,000)^(1/3) - 1 = 1.44^0.333 - 1 ≈ 12.9%/年。
短期和长期资本利得税有什么区别？
持有期不超过 1 年的收益为短期资本利得，按普通所得税率征税（可能高达 37%）；持有超过 1 年的收益为长期资本利得，适用更低的优惠税率（0%、15% 或 20%，取决于收入水平）。本计算器可帮助您估算税前和税后利润。
买入价和成本基础有什么区别？
成本基础（Cost Basis）不仅包含买入价，还应包括所有交易手续费、股票分拆/合并调整，以及股息再投资购入的股份成本。准确的成本基础对计算应税收益至关重要，可避免多缴税款。
How to Calculate Stock Profit and Loss
Stock profit is the money you keep after selling shares for more than you paid. This calculator factors in purchase price, selling price, shares sold, brokerage commissions, and capital gains tax so you can see your true net return from any trade.
Stock Profit Formula
Every stock trade comes down to three numbers: what you paid, what you received, and what you lost to fees and taxes. Here are the core formulas:
Gross Profit
This ignores commissions and taxes.
Net Profit (Before Tax)
Where Total Investment = Buy Price × Shares + Buy Commission, and Total Sale = Sell Price × Shares − Sell Commission.
After-Tax Profit
Tax applies only when net profit is positive. Losses are not taxed (and may offset other gains).
Worked Example
- Buy 200 shares at $50 (Total cost: $10,000)
- Buy commission: $9.99 flat
- Sell all 200 shares at $65 (Gross proceeds: $13,000)
- Sell commission: $9.99 flat
- Total Investment: $10,000 + $9.99 = $10,009.99
- Total Sale: $13,000 − $9.99 = $12,990.01
- Net Profit: $12,990.01 − $10,009.99 = $2,980.02
- At 15% tax: $2,980.02 × 0.15 = $447.00 tax, leaving $2,533.02 after tax
Calculating Profit on Partial Sales
You do not always sell all your shares at once. When selling a portion of your position, the calculator allocates your buy-side costs proportionally to the shares being sold.
For percentage-based commissions, the allocation happens automatically because the commission is calculated on the number of shares sold. For flat-fee commissions, the full fee is charged per transaction regardless of how many shares you sell.
How Brokerage Commissions Affect Your Profit
Commissions are transaction fees charged by your broker on each trade. They come in two forms:
| Type | How It Works | Example |
|---|---|---|
| Percentage | A % of the trade value | 0.1% on a $10,000 trade = $10 |
| Flat fee | Fixed dollar amount per trade | $4.95 per trade regardless of size |
| Zero commission | No fee (common at US brokers) | $0 per stock trade at Fidelity, Schwab, etc. |
Percentage Commission Formula
Total Trade Cost
Tip: Even with zero-commission brokers, other costs like SEC fees, TAF fees, and bid-ask spreads still exist. These are typically very small but can matter for high-frequency or large-volume traders.
Understanding Capital Gains Tax on Stocks
When you sell stock at a profit in the United States, the IRS taxes the gain. The rate depends on how long you held the stock before selling.
Short-Term Capital Gains (Held 1 Year or Less)
Short-term gains are taxed as ordinary income. For the 2026 tax year, the federal rates are:
| Tax Rate | Single Filer Income | Married Filing Jointly |
|---|---|---|
| 10% | Up to $11,925 | Up to $23,850 |
| 12% | $11,926 – $48,475 | $23,851 – $96,950 |
| 22% | $48,476 – $103,350 | $96,951 – $206,700 |
| 24% | $103,351 – $197,300 | $206,701 – $394,600 |
| 32% | $197,301 – $250,525 | $394,601 – $501,050 |
| 35% | $250,526 – $626,350 | $501,051 – $751,600 |
| 37% | Over $626,350 | Over $751,600 |
Long-Term Capital Gains (Held More Than 1 Year)
Long-term gains are taxed at reduced rates for 2026:
| Tax Rate | Single Filer Income | Married Filing Jointly |
|---|---|---|
| 0% | Up to $48,350 | Up to $96,700 |
| 15% | $48,351 – $533,400 | $96,701 – $600,050 |
| 20% | Over $533,400 | Over $600,050 |
Net Investment Income Tax (NIIT): An additional 3.8% tax applies to net investment income for single filers earning over $200,000 or married couples earning over $250,000. This is on top of the regular capital gains rate.
Calculating Return on Investment (ROI)
ROI tells you how efficiently your capital was used, expressed as a percentage. It lets you compare investments of different sizes on equal footing.
ROI Formula (Before Tax)
ROI Formula (After Tax)
Annualized ROI
Use annualized ROI to compare investments held for different time periods.
How to Find Your Break-Even Price
The break-even price is the minimum sell price at which you recover your entire investment, including all commissions. Selling above break-even means profit; selling below means a loss.
Break-Even with Flat Sell Commission
Break-Even with Percentage Sell Commission
Example
You buy 100 shares at $50 with a $10 flat buy commission. Total Investment = $5,010. If the sell commission is also $10 flat: Break-Even = ($5,010 + $10) / 100 = $50.20. The stock must rise above $50.20 for you to turn a profit.
When Should You Sell Your Stocks?
There is no single answer, but a structured decision framework helps remove emotion from the process:
Reasons to Consider Selling
- Target reached: The stock has hit your pre-set price or ROI target
- Thesis broken: The reason you bought no longer applies (e.g., declining fundamentals)
- Rebalancing: A single position has grown too large relative to your portfolio
- Tax-loss harvesting: Selling a loser to offset gains before year-end
- Better opportunity: Capital is needed for a higher-conviction investment
Common Mistakes to Avoid
- Panic selling during a broad market correction
- Holding indefinitely without reviewing your thesis
- Ignoring tax implications (short-term vs long-term holding period)
- Selling winners too early while holding losers too long (disposition effect)
Stock Return Benchmarks: What Is a Good Return?
Understanding historical returns helps you set realistic expectations and evaluate your performance:
| Benchmark | Avg. Annual Return | Notes |
|---|---|---|
| S&P 500 (nominal) | ~10% | Long-term average since 1926 |
| S&P 500 (real, after inflation) | ~7% | Adjusted for ~3% average inflation |
| US bonds (aggregate) | ~5% | Bloomberg US Aggregate Bond Index |
| Savings account | ~4–5% | High-yield savings, 2024–2026 |
| Inflation (US CPI) | ~3% | Long-term historical average |
A stock returning 15–20% annually is considered strong. If your portfolio consistently beats the S&P 500 after fees and taxes, you are outperforming the majority of professional fund managers. Use our Compound Interest Calculator to project future growth.