Capital gains & loss calculator
Estimate the tax on a sale — and see how much of a gain a losing position could shelter.
Short-term vs long-term — why it matters
In the US, how long you held the position before selling changes the tax rate a lot. Sell within a year and the profit is a short-term gain, taxed as ordinary income at your regular bracket. Hold past a year and it becomes a long-term gain, taxed at the preferential rates of 0%, 15%, or 20% for most people.
That gap is why "am I a few weeks away from the one-year mark?" is a question worth asking before you sell a winner.
When the number is negative
A loss isn't only a loss. Realized capital losses offset your capital gains dollar-for-dollar, and if your losses exceed your gains you can deduct up to $3,000 against ordinary income per year, carrying the rest forward. This calculator shows the loss as a positive "offset" — the amount of gains it could cancel out.
Just watch the wash-sale rule if you plan to rebuy.
Rough estimate for US federal tax, educational only — it ignores state tax, the 3.8% net investment income tax, and your full situation. Not tax advice. Runs entirely in your browser.