Stock Profit/Loss Calculator
Calculate gross and net P&L, capital gains tax, and after-tax profit for any stock trade.
Short-Term vs. Long-Term Capital Gains
The holding period of a stock determines which tax rate applies to your gain. Short-term gains (held less than 1 year) are taxed as ordinary income at your marginal rate — the same rate as your salary. Long-term gains (held more than 1 year) receive preferential rates: 0%, 15%, or 20% depending on your income level. For most investors, holding a position longer than one year before selling can meaningfully reduce the tax bill.
Long-Term Capital Gains Rates (2024)
0% rate: taxable income up to $47,025 (single) / $94,050 (married). 15% rate: income up to $518,900 (single) / $583,750 (married). 20% rate: above those thresholds. High-income earners may also owe the 3.8% Net Investment Income Tax (NIIT).
The Wash Sale Rule
If you sell a stock at a loss and repurchase it (or a "substantially identical" security) within 30 days before or after the sale, the IRS disallows the loss under the wash sale rule. The loss is not simply lost — it is added to the cost basis of the repurchased shares, deferring the deduction until you sell with a longer gap.
How Commissions Erode Small Gains
On a 100-share trade worth $500, a $10 commission on each side ($20 total) eats 4% of your investment before any price movement. Zero-commission brokers have reduced this for most retail investors, but hidden costs like wide bid-ask spreads can still matter on small-cap or thinly-traded stocks.