Capital Gains Tax Calculator (2026)
Model one stock sale using official 2026 federal rates and a flat state-rate assumption. The subtotal excludes NIIT and other return-level adjustments.
After deductions, excluding this gain. Assumes no other capital gains or qualified dividends.
Enter all inputs and calculate to see a scenario. Zero amounts are allowed.
How the single-sale calculation works
Enter the total adjusted basis of the shares sold and the total disposal proceeds after selling fees. Gain or loss equals proceeds minus basis. Use ordinary taxable income before this sale, after applicable deductions. Zero is a valid amount; an empty input does not mean zero.
For a positive short-term gain, the federal estimate is tax on income plus gain minus tax on income alone. For a long-term gain, the same incremental calculation stacks the gain above ordinary taxable income across the 0%, 15% and 20% bands. The model assumes no other capital gains or qualified dividends.
For example, a single filer with $49,000 of ordinary taxable income and a $2,000 long-term gain in 2026 has $450 of that gain within the zero-rate band and $1,550 at 15%, producing $232.50 before other taxes or adjustments. This is a formula illustration, not a recommendation to sell.
Holding period and limits
Under the general rule, one calendar year or less is short-term and more than one year is long-term. Lower federal rates may apply to qualifying long-term gains, but delaying a sale does not guarantee a lower total tax bill or better investment outcome. Gifted, inherited, collectible, real-estate and specially treated stock transactions require different analysis.
The optional state input multiplies positive gain by the rate you enter. It does not select a jurisdiction or calculate its progressive brackets. NIIT, AMT, loss netting, loss carryovers, wash sales, deduction changes, credits and local taxes are not included. The displayed proceeds are reduced only by the modeled subtotal, not every possible tax.
Official sources
- IRS Revenue Procedure 2025-32: published 2026 ordinary and capital-gain thresholds
- IRS capital gains and losses, including holding periods
- IRS NIIT: an additional tax not calculated here
Frequently Asked Questions
Which tax year and rates are used?
This page uses the official 2026 ordinary-income and long-term capital-gain thresholds in IRS Revenue Procedure 2025-32, published in 2025. They are not projections. The calculation is a simplified single-sale estimate, not a complete tax return.
What income amount should I enter?
Enter ordinary taxable income after applicable deductions and before this sale. This model assumes no other capital gains or qualified dividends. Enter an amount, not your salary or the top of an income range.
Does exactly one year qualify for long-term treatment?
Generally no. More than one calendar year is long-term; one year or less is short-term. The usual count begins the day after acquisition and includes the disposal date. Inherited, gifted and other special-property rules are outside this calculator.
How should I enter cost basis and proceeds?
Enter total adjusted basis for the shares sold and total sale proceeds net of selling fees, not per-share prices. Include applicable acquisition costs in basis. This page does not determine tax-lot basis, wash-sale adjustments or corporate-action adjustments for you.
Does this estimate all taxes on the sale?
No. The displayed subtotal includes the modeled federal capital-gain tax and your user-entered flat state-rate assumption. It excludes NIIT, AMT, local taxes, deduction changes and credits. Actual state taxes can be progressive and use different income definitions.
What happens if the sale produces a loss?
The signed loss remains visible, but the tax subtotal for that sale is zero. This page does not calculate loss netting, deduction limits, carryovers or a tax refund. Other transactions may change your overall tax liability.
Compare Tax-Lot Scenarios
A single-sale estimate does not select which shares to sell. Compare lot-selection assumptions separately and confirm the required identification with your broker before a transaction.
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