Capital Gains Tax Calculator 2026: Rates, Thresholds and Examples

What a 2026 capital gains tax calculator tells you

If you sold stocks, a mutual fund or property at a profit this year, a capital gains tax calculator answers one question: what rate applies to your gain? For assets held more than one year (long-term gains), the 2026 federal rate is 0%, 15% or 20% — not the higher ordinary-income rates that apply to wages. Which one you pay depends on your total taxable income, because your gain stacks on top of your other income.

The 0% band is larger than most people expect. In 2026 a single filer pays 0% on long-term gains until total taxable income reaches $49,450; for married couples filing jointly the 0% band runs up to $98,900. Above those points the rate steps up to 15%, and only very high incomes reach 20%. A good calculator does this stacking math for you and flags the extra 3.8% Net Investment Income Tax (NIIT) that can apply to higher earners.

Two things this estimate does not include: state capital gains tax (many states tax gains as ordinary income) and gains on assets held one year or less, which are short-term and taxed at your ordinary bracket instead. Both are covered below.

2026 long-term capital gains rate thresholds

These are the 2026 breakpoints from IRS Revenue Procedure 2025-32. The dollar figures are the top of each taxable-income band, and your long-term gain is measured where it lands after being stacked on your ordinary income.

Married filing separately has a 0% ceiling of $49,450 and a 15% ceiling of $306,850. Estates and trusts hit the 15% rate above just $3,300 and the 20% rate above $16,250 — one reason gains are often distributed to beneficiaries.

Short-term vs long-term: the holding period changes everything

The single biggest factor in your rate is how long you owned the asset. Sell after one year or less and the gain is short-term, taxed at your ordinary 2026 income bracket (10% to 37%). Hold for more than a year and you qualify for the preferential long-term rates above.

For a single filer, the top 37% bracket begins above $640,600 of taxable income in 2026 ($768,700 married filing jointly). Waiting to cross the one-year mark can therefore cut the rate on a large gain by more than half — from 37% down to 20% or less.

Worked examples: how stacking sets your rate

These examples use 2026 single-filer thresholds and assume the figures shown are taxable income (after deductions).

• Mostly 0% (modest income). Ordinary taxable income $30,000, long-term gain $20,000. The gain stacks from $30,000 to $50,000. Everything up to $49,450 is taxed at 0%, so the first $19,450 of the gain pays nothing; only the last $550 falls into the 15% band = about $83 of tax.
• Straight 15% (middle income). Ordinary taxable income $70,000, long-term gain $30,000. Ordinary income already exceeds the $49,450 zero-rate ceiling, so the whole $30,000 gain is taxed at 15% = $4,500.
• 20% plus NIIT (high income). Ordinary taxable income $600,000, long-term gain $100,000. The gain sits above the $545,500 breakpoint, so it is taxed at 20% = $20,000, and because income is over $200,000 the 3.8% NIIT adds $3,800 — a combined $23,800.

The pattern: your ordinary income fills the lower bands first, then your gain is layered on top. That is why two people with the same gain can owe very different amounts.

The 3.8% NIIT and the home-sale exclusion

Two federal rules change the answer for many filers, so a capital gains estimate should account for both.

Net Investment Income Tax (NIIT). On top of the 0/15/20% rate, a 3.8% surtax applies to net investment income once modified adjusted gross income exceeds $200,000 (single or head of household), $250,000 (married filing jointly), or $125,000 (married filing separately). These thresholds are set by statute and are not indexed for inflation, so more taxpayers cross them over time.

Sale of your main home. If you sell your primary residence, you can exclude up to $250,000 of gain from income ($500,000 on a joint return), provided you owned and lived in the home for at least 24 months (2 of the last 5 years) before the sale. Only gain above the exclusion is taxable — so a couple with a $400,000 gain on their main home may owe nothing. Subtract the eligible exclusion first, then apply the rate table to whatever remains.