Estimate federal tax on long-term and short-term gains, plus the 3.8% NIIT and your state
| Taxable Income (incl. gains) | Single | Married Filing Jointly | Head of Household | Rate |
|---|---|---|---|---|
| Up to the 0% ceiling | $48,350 | $96,700 | $64,750 | 0% |
| 0% ceiling to 15% ceiling | $48,350 – $533,400 | $96,700 – $600,000 | $64,750 – $566,700 | 15% |
| Above the 15% ceiling | $533,400+ | $600,000+ | $566,700+ | 20% |
Short-term gains don't get this schedule. They stack on your ordinary income at 10% to 37%, the same as wages. The 3.8% NIIT adds on once modified AGI passes $200,000 single or $250,000 married filing jointly. Thresholds move most years with inflation.
| State | Top Rate on Gains | Notes |
|---|---|---|
| California | 13.3% | Gains taxed as ordinary income |
| New Jersey | 10.75% | Ordinary income rates |
| New York | 10.9% | State portion; NYC adds more |
| Oregon | 9.9% | Ordinary income rates |
| Minnesota | 9.85% | Ordinary income rates |
| Washington | 7% excise | Only on long-term gains above ~$278,000; no ordinary income tax |
| TX, FL, NV, TN, SD, NH, WY, AK | 0% | No state income tax on gains |
Most states treat capital gains as ordinary income, so your marginal rate depends on where the gain lands in your state's brackets. Enter your top state rate above for a ballpark; the calculator applies it to your whole gain, which slightly overstates it if part of the gain falls in lower brackets.
Sell something for more than you paid and the profit is a capital gain: long-term if you held it over a year, short-term if not. Those two categories are taxed on completely different schedules, and picking the wrong one is the most common mistake people make when estimating. This calculator stacks your income and gains the way the IRS does, then applies 2025 federal brackets, the NIIT, and a state estimate you control.
Ordinary income fills the regular 10% to 37% brackets first. Short-term gains join it there. Long-term gains then stack on top at their own 0%, 15%, or 20% breakpoints, which is why a large gain can span two long-term rates. Finally, the 3.8% NIIT applies to the smaller of your net investment income or the amount your modified AGI exceeds $200,000 single / $250,000 joint.
Enter your taxable income before gains (salary minus standard or itemized deductions is close enough), then split your gain into long-term and short-term pieces. If you're estimating a crypto year, add up every profitable disposal separately by holding period. The state field defaults to 0; set it to your state's top rate from the table below for a rough add-on.
A single filer with $75,000 of taxable income sells $25,000 of index fund shares held for three years. The gain stacks income from $75,000 to $100,000, entirely inside the 15% band ($48,350 to $533,400), so federal tax is 0.15 × $25,000 = $3,750. MAGI of $100,000 is under the $200,000 NIIT threshold, so nothing more is owed federally. Effective rate: 15.0%, and they keep $21,250.
Bump the same person to $210,000 of income with an $80,000 long-term gain and two things change. The gain spans $210,000 to $290,000, still all in the 15% band, so that part is $12,000. But MAGI now exceeds $200,000 by $90,000, and since the $80,000 gain is smaller than the excess, the NIIT applies to the whole gain: $80,000 × 3.8% = $3,040. Total: $15,040, an 18.8% effective rate. That 3.8% surtax surprises a lot of people the first year they cross the line.
Crypto follows the same long-term/short-term split, with three twists worth knowing. Every trade counts: swapping BTC for ETH is a disposal of the BTC, taxable at that moment's value, not just cash-outs to dollars. Wash sales don't currently apply, since the rule covers stocks and securities rather than property, so loss harvesting by selling and rebuying is on the table under current law. And starting with tax year 2025, US brokers report digital asset proceeds on Form 1099-DA, which means the IRS gets the same numbers you do.
This is a planning estimate using 2025 federal brackets, not tax advice. It ignores items like the 25% unrecaptured section 1250 rate for rental real estate, the 28% collectibles rate, depreciation recapture, and carryforwards. For anything with moving parts, run it past a CPA.
Long-term gains (assets held over one year) are taxed at 0%, 15%, or 20% depending on total taxable income. For 2025, a single filer pays 0% on taxable income up to $48,350, 15% up to $533,400, and 20% above that. For married couples filing jointly the breakpoints are $96,700 and $600,000. Short-term gains are taxed as ordinary income at your regular bracket rate, which runs from 10% to 37%.
The IRS treats crypto as property, so every sale, swap for another token, or spend is a taxable event. Holding for more than a year earns the long-term rates; trading sooner means ordinary income rates on the gain. Starting with tax year 2025, brokers report digital asset proceeds on Form 1099-DA. One quirk: the wash-sale rule covers stocks and securities, not property, so under current law you can sell at a loss and rebuy immediately to harvest the loss.
If your modified adjusted gross income exceeds $200,000 as a single filer or $250,000 filing jointly, the NIIT applies at 3.8% on the smaller of your net investment income or the amount over the threshold. A single filer with $210,000 of income and an $80,000 gain owes 3.8% on $80,000, which is $3,040, because the gain is smaller than the $10,000 excess.
Four levers work for most people. Hold winners past the one-year mark to swap ordinary rates for the 0/15/20% schedule. Realize gains in a low-income year to land in the 0% bracket. Harvest losses to offset gains plus up to $3,000 of ordinary income. And trade inside tax-advantaged accounts like a 401(k), IRA, or Roth, where gains aren't taxed as you go.
The line is one year, measured from acquisition date to sale date. At one year or less, the gain is short-term and taxed as ordinary income. Past a full year it's long-term and taxed at 0%, 15%, or 20%. The gap is real money: a $36,000 gain stacked on $82,000 of income costs $8,213 as a short-term gain but $5,400 as a long-term one, a $2,813 reward for waiting.
Most states tax capital gains as ordinary income. California tops out at 13.3%, New Jersey at 10.75%, New York at 10.9%, and Oregon at 9.9%. Nine states levy no income tax at all, though Washington charges a 7% excise tax on long-term gains above roughly $278,000. The state line in this calculator is an estimate applied to your whole gain, so treat it as a ballpark.