Capital Gains Tax Calculator | Short-Term vs Long-Term Rates

You sold something for a profit. Now the IRS wants to know one thing: how long did you hold it?

That single question decides your tax rate more than almost anything else in investing. Sell a stock after 11 months and the profit gets taxed like your salary. Sell it after 13 months and the same profit can get taxed at nearly half the rate. The asset didn’t change. The profit didn’t change. Only the calendar changed.

It’s the highest-leverage tax decision most investors ever make, and it costs nothing to get right. Enter your sale in the calculator above and it shows both versions side by side: what you owe as a short-term gain versus a long-term one.

Short-term vs long-term: the one-year line

The IRS draws the line at one year, and it means it precisely. Hold an asset one year or less and the gain is short-term, taxed at your ordinary income rate (10% to 37%, same brackets as your wages). Hold it more than one year and the gain is long-term, taxed at the preferential rates of 0%, 15%, or 20%.

“More than one year” is doing real work in that sentence. The holding period starts the day after you buy. Buy on January 1 and sell on January 1 of the next year, and that’s exactly one year. Still short-term. You need to hold until at least January 2 for long-term treatment. One day of impatience has cost people five figures.

Also worth knowing: you only owe tax when you sell. If your stock doubles and you keep holding, that profit is “unrealized” and the tax bill is zero. No sale, no taxable event. That’s why long-term investors can let winners compound for years without the IRS taking a cut along the way.

A worked example with real numbers

You buy 100 shares at $80 ($8,000 total). Fourteen months later you sell at $130 ($13,000). Your gain is $5,000, and because you held more than a year, it’s long-term.

Say you’re a single filer whose other taxable income is $70,000. That puts the entire $5,000 gain inside the 15% long-term bracket for 2026. Your tax on the gain: $750.

Now imagine you’d sold at 11 months instead. Same $5,000 profit, but short-term, taxed as ordinary income. At a 22% marginal rate, that’s $1,100.

Same stock. Same profit. A $350 difference, purely from the calendar. Scale that up to a $50,000 gain and the gap between 15% and 37% is $11,000. Holding isn’t just patience. It’s a tax strategy.

The 2026 long-term capital gains brackets

Your long-term rate depends on your taxable income including the gain, since the gain stacks on top of your other income. For 2026 (per IRS Revenue Procedure 2025-32):

• Single: 0% up to $49,450 of taxable income, 15% to $545,500, 20% above that
• Married filing jointly: 0% up to $98,900, 15% to $613,700, 20% above that

Yes, the 0% bracket is real. If your total taxable income stays under the threshold, your long-term gains are taxed at literally zero percent. This is why retirees in low-income years and young investors just starting out can harvest gains strategically.

One more layer for high earners: the 3.8% Net Investment Income Tax kicks in above $200,000 of income ($250,000 married filing jointly). So the true top rate on long-term gains can reach 23.8%, and short-term gains can hit 40.8%.

Losses count too (and they’re useful)

Not every sale is a winner, and the tax code softens the blow. Capital losses offset capital gains dollar for dollar. If your losses exceed your gains, you can deduct up to $3,000 of the excess against ordinary income each year, and carry the rest forward indefinitely.

This is the engine behind tax-loss harvesting: selling losers before year-end to offset winners, then (if you still like the asset) buying back after 30 days to avoid the wash-sale rule. Done systematically, it’s one of the few reliable ways to shave real money off your tax bill without changing your investment strategy.

How to legally pay less

Hold past the one-year mark. The single biggest lever. If you’re close to the line, waiting a few weeks can cut your rate nearly in half.

Time your sales into low-income years. Between jobs, early retirement, a sabbatical: years with little other income are golden for realizing long-term gains, possibly at 0%.

Harvest losses deliberately. Don’t just hold losers out of hope. Sell them, bank the loss against your gains, and redeploy the cash.

Use the right accounts. Gains inside a 401(k), IRA, or HSA aren’t taxed when realized at all. Your taxable brokerage account should hold your most tax-efficient, longest-held positions. If your income is too high to fund a Roth IRA directly, the backdoor Roth IRA calculator estimates the conversion tax involved in getting money in through the back door, so it can grow and eventually come out untaxed.

Give appreciated stock instead of cash. Donating shares you’ve held over a year to charity generally lets you deduct the full market value without ever paying tax on the gain. It’s the closest thing to a legal double benefit in the tax code.

If some of your income comes from freelancing or a side business, remember you’re probably paying self-employment tax on that money too, on top of whatever this sale costs you. The self-employment tax calculator estimates that separate bill so the two don’t blur together at tax time.

What the calculator assumes

• Gain = sale price minus cost basis (what you paid, including commissions).
• Long-term means held more than one year. Short-term is taxed at the ordinary marginal rate you enter.
• Federal tax only. States do their own thing: some have no capital gains tax, others tax gains as ordinary income.
• Doesn’t model the 3.8% Net Investment Income Tax or the alternative minimum tax. High earners should add those mentally.

This calculator gives an educational estimate, not tax advice. Capital gains interact with your full return, so consult a qualified tax professional before making moves.