Capital Gains Tax Calculator

How federal and state capital gains tax works

When you sell stock, funds, crypto, or land for more than your cost basis, the profit is a capital gain. Under 26 U.S.C. § 1222, your holding time sets the tax rules. As IRS Topic No. 409 states, "Generally, if you hold the asset for more than one year before you dispose of it, your capital gain or loss is long-term." If you hold it 1 year or less, your gain or loss is short-term. You start counting on the day after you buy the asset, and the day you sell counts as your last day. For market trades, IRS Publication 550 states that "your holding period begins the day after the trade date you bought the securities, and ends on the trade date you sold them." Check your exact settlement day in the stock trade settlement date calculator.

Short-term capital gains get no lower tax rate. They sit on top of your regular taxable income and pay the seven ordinary rates from 10% to 37% under 26 U.S.C. § 1(j). First, you subtract your deduction from your other income. In 2026 (IRS Revenue Procedure 2025-32 § 4.14), the standard deduction is $16,100 for Single or Married Filing Separately. It is $32,200 for Married Filing Jointly or Qualifying Surviving Spouse, and $24,150 for Head of Household. In 2025 (26 U.S.C. § 63(c)(7); Revenue Procedure 2025-32 § 3.01), those amounts are $15,750, $31,500, and $23,625. See how wage income fills the seven brackets in the federal income tax calculator.

Regular long-term capital gains use three lower rates under 26 U.S.C. § 1(h): 0%, 15%, and 20%. Your ordinary taxable income (other income minus your deduction) fills the bottom of the tax scale first. Your long-term gain then stacks on top of that base on the Form 1040 worksheet. For 2026 (Revenue Procedure 2025-32 § 4.03), the zero-rate ceiling is $49,450 for Single or Separate filers. It covers up to $98,900 for Joint or Surviving Spouse filers, and $66,200 for Head of Household. Next, the middle tier runs up to $545,500 Single, $613,700 Joint or Surviving Spouse, $306,850 Separate, and $579,600 Head of Household. Gains above those ceilings pay the top rate.

For 2025 (Revenue Procedure 2024-40 § 2.03), the zero-rate ceiling is $48,350 Single or Separate, $96,700 Joint or Surviving Spouse, and $64,750 Head of Household. The 2025 middle-tier ceiling is $533,400 Single, $600,050 Joint or Surviving Spouse, $300,000 Separate, and $566,700 Head of Household. Because wages fill the bottom space first, a high salary can push your whole gain out of the zero-tax band. That happens even when the gain itself is small. Dividend investors can check the more-than-60-days-in-121-days holding test under 26 U.S.C. § 1(h)(11) for those three preferential tiers in the qualified dividend holding period calculator.

Capital gains stacking and NIIT formula

Realized gain (or loss) = sale proceeds − adjusted basis
Taxable income without sale = max(0, other income − deduction)
Taxable income with sale = max(0, other income + max(0, gain) − deduction)
Regular LTCG stacks above ordinary taxable income across 0% / 15% / 20% (or 25% / 28% Schedule D caps)
NIIT = 3.8% × min(max(0, gain), max(0, MAGI − NIIT threshold))
Total capital gains tax = federal CGT + 3.8% NIIT + round(max(0, gain) × state rate)

Worked 2026 capital gains tax examples

Default 15%-tier sale ($50,000.00 cost, $80,000.00 sale, $95,000.00 other pay, 5% state rate): Your long-term gain is $80,000.00 − $50,000.00 = $30,000.00. Taking the $16,100 standard deduction from $95,000.00 leaves $78,900.00 of ordinary taxable income, above the zero-rate band. All $30,000.00 sits in the 15% tier ($78,900.00 to $108,900.00) for $4,500.00 of federal tax. State tax adds $1,500.00, so total tax is $6,000.00 (20.00% of the gain) and net cash is $74,000.00. Sold in 1 year or less, that $30,000.00 short-term gain spans the 22% bracket ($26,800.00 up to $105,700.00 = $5,896.00) and 24% bracket ($3,200.00 above $105,700.00 = $768.00) for $6,664.00 of federal tax. Holding past 1 year saves $2,164.00.

Straddling the zero-rate and 15% brackets ($30,000.00 cost, $70,000.00 sale, $45,000.00 other pay, no state tax): Your long-term gain is $40,000.00 and ordinary taxable income is $28,900.00. Up to the $49,450 Single ceiling, your first $20,550.00 of gain pays no federal tax. The remaining $19,450.00 ($40,000.00 − $20,550.00) pays 15% for $2,917.50 of total tax. That is an effective rate of 7.29% on the $40,000.00 gain.

NIIT threshold straddle (modeled on IRS NIIT Q&A #20, with a $90,000.00 gain: $180,000.00 wages, no state tax): Total MAGI is $180,000.00 + $90,000.00 = $270,000.00. That beats the Single line by $70,000.00. Since $70,000.00 is less than the $90,000.00 gain, the 3.8% NIIT applies only to $70,000.00. That adds $2,660.00 of NIIT to the $13,500.00 regular long-term tax, for $16,160.00 of federal tax including NIIT.

Net capital loss cap and carryforward ($50,000.00 cost, $35,000.00 sale, $95,000.00 other pay): Your net capital loss is $15,000.00, so capital gains tax is $0.00. On Schedule D, $3,000 cuts your ordinary income to $75,900.00. That saves $660.00 of federal tax this year, while $12,000.00 carries forward to future tax years.

Scope, limits, and assumptions

• Models one asset sale or net Schedule D position for tax years 2025 (Rev. Proc. 2024-40), 2026 (Rev. Proc. 2025-32) and 2027 (Rev. Proc. 2026-35) across all 5 filing statuses. Standard Deduction uses the basic standard deduction for your status. If you claim age-65 or blind boxes under 26 U.S.C. § 63(f) ($2,050 unmarried or $1,650 married per box in 2026), switch to Itemized and enter your combined deduction.
• If you have multiple trades on Form 8949, Schedule D Part I and Part II net short-term and long-term buckets first. Then the return applies the tax worksheets. Your other income stands in for modified AGI before the sale, while foreign pay exclusions under 26 U.S.C. § 911 add back to MAGI.
• The capped-rate options tax the whole gain you enter at their cap. A building sale with $400,000 of gain, of which $100,000 is depreciation, needs two runs: enter only the $100,000 of depreciation under the capped option, then the rest as a regular gain. The page does not compute the exclusion for qualified small business stock either, so enter only the part that stays taxable. Use the rental property sale tax calculator and the QSBS exclusion calculator for those splits.
• Prior-year capital loss carryovers are not an input. Net them against this sale first, as Schedule D does, and enter the net result. The capital loss carryover calculator tracks them.
• Federal tax is figured from the rate schedules at your exact taxable income. A filed Form 1040 with taxable income under $100,000 uses the Tax Table, which taxes each $50 row at its midpoint, so the return can differ from this page by a few dollars.
• Home sale exclusions up to $250,000 ($500,000 joint) under 26 U.S.C. § 121 are outside this form. Test a home sale in the home sale exclusion calculator or a property swap in the 1031 exchange calculator.
• State tax is a flat rate on positive net gain from 0% to 15% and $0.00 on net losses. State exemptions or surtaxes are in the Washington capital gains tax calculator.

These figures are estimates for learning and planning, not financial, tax, legal or investment advice. Terms of use.

What to do with your estimate

Check your trade date before selling near the 1-year mark. A sale on the first anniversary of your purchase date is still short-term; a sale on the next day or later is long-term. In the default example, that one extra day moves the gain out of the short-term brackets ($6,664.00 federal tax) and saves $2,164.00.

Fill unused zero-bracket space in low-income years. In 2026, a joint couple taking the standard deduction can reach $131,100 of total AGI ($32,200 deduction plus $98,900 ceiling). They owe $0.00 of federal capital gains tax.

Set aside cash from your After-Tax Proceeds and pay quarterly tax when needed. Brokerage sales on Form 1099-B have no payroll withholding. Test your payments in the quarterly estimated tax calculator if you will owe $1,000 or more under 26 U.S.C. § 6654(e)(1).

Capital gains tax questions