Federal long-term gain estimate

2026 Capital Gains Tax Calculator

Enter sale price, purchase cost and other income; TaxMathKit calculates the gain and estimates 2026 short- or long-term federal tax automatically.

2026 thresholdsRates: 2026Updated August 10, 2026
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The example shows the required inputs. Replace only the values that apply to you.

Saved only on this devicePlanning estimate
Your inputs
Enter the details you haveTell us what you paid, what you received and your other income. We calculate the gain, standard deduction, capital-gain bands and simplified NIIT automatically.
Add selling costs or a prior capital lossOptional
Estimated result
Estimated federal gain tax$6,000
Net gain used$40,000
Effective rate on gain15.0%
Gain taxed at 0%$0
Gain taxed at 15%$40,000
Gain taxed at 20%$0

Federal planning estimate. State tax, depreciation recapture and special gain categories are excluded.

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How it works

Capital gains stacking

Formula

Long-term gains sit above ordinary taxable income, filling available 0%, then 15%, then 20% capital-gain bands.

Enter facts normally available from the transaction: proceeds, original cost, selling fees, holding period and other yearly income. The calculator derives the net gain and ordinary taxable-income starting point.

The NIIT estimate is simplified. State taxes, collectibles, depreciation recapture and home-sale exclusions are outside this calculator.

Assumptions and limits

  • Federal individual tax
  • Net long-term gain is eligible for preferential rates
  • Standard deduction applied to other income
  • No special 25% or 28% gain category
Planning estimate, not tax advice

Tax law depends on facts this tool cannot collect. Do not use the result as the sole basis for filing, withholding or payment decisions.

Frequently asked questions

Why does ordinary income affect my capital gains rate?

Preferential gain bands are shared with ordinary taxable income. Ordinary income fills the lower space before long-term gains are stacked on top.

How are short-term gains taxed?

Short-term gains are generally taxed at ordinary federal income-tax rates.