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Capital Gains Tax Estimator

The Capital Gains Tax Estimator measures gain or loss on an asset sale and applies separate user-entered rates to short-term and long-term portions. It accounts for purchase cost, improvement or acquisition costs, selling expenses, and the amount assigned to each holding-period category.

This structure is useful for screening a stock, property, business interest, or other asset disposal before a transaction. The calculator does not determine legal basis rules or holding-period classifications; those inputs must come from the records and rules that apply to the asset.

Estimate inputs

USD
USD
USD
USD
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USD
Result
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Estimated capital gains tax
Net gain or loss—
Long-term gain—
Short-term gain—
After-tax sale proceeds—

1. Enter sale proceeds

Use the amount received before subtracting selling costs.

2. Build adjusted basis

Enter original purchase price and qualifying basis additions.

3. Include selling costs

Add commissions, legal fees, or other costs allocated to the sale.

4. Split the gain

Set the percentage treated as long-term; the remainder is treated as short-term.

5. Apply rates and offsets

Enter applicable rates and any allowable loss offsets already determined.

6. Review gain and tax

Check net gain, the term split, and after-tax proceeds.

Adjusted basis = Purchase price + Basis adjustments Net gain = Sale proceeds − Selling costs − Adjusted basis − Loss offsets Long-term tax = Positive net gain × Long-term share × Long-term rate Short-term tax = Positive net gain × (1 − Long-term share) × Short-term rate

A negative net gain is displayed as a loss and produces zero estimated tax in this screening model.

What the result means

The main result is an estimate based entirely on the values and rates entered. Use the supporting rows to see the taxable base and major components.

Results are planning estimates only. Tax rules, exemptions, filing obligations, and rates vary by jurisdiction and may change; verify the figures with the relevant tax authority or a qualified adviser.

Given: $120,000 proceeds, $80,000 purchase price, $5,000 basis additions, $3,000 selling costs, all long-term, a 15% rate, and no loss offset.

Calculation: Adjusted basis = $85,000. Net gain = $120,000 − $3,000 − $85,000 = $32,000. Tax = $32,000 × 15% = $4,800.

Result: Estimated capital gains tax is $4,800.

What belongs in adjusted basis?

Use the original cost plus only additions allowed by the rules for the asset, such as certain improvements or acquisition costs.

What if the sale produces a loss?

The calculator shows the loss and sets tax to zero; it does not calculate carryovers or limits on loss deductions.

How do I classify long-term and short-term gain?

Use the holding-period rules for your jurisdiction and asset type, then enter the long-term percentage.

Are depreciation recapture or surtaxes included?

No. Add their effect only through a separately determined rate or use a specialized calculation.

Why subtract selling costs?

Eligible selling costs reduce net proceeds and may reduce the gain used in the estimate.