Adjusted cost basisHigh modeled impact
Little modeled change near this scenario
Basis helps determine whether the entered sale creates a loss.
Invest · Tax planning
Tax-Loss Harvesting Estimator
Estimate a capital loss, the portion matched against entered gains, and its approximate current tax value.
Your result
Estimated harvested loss
—
Usable against entered gains—
Estimated current tax value—
Net current benefit—
Through the Lens
What drives this result?
Controlled, deterministic sensitivity around your current inputs reveals which assumptions move the estimated current net benefit most.
Sale proceedsHigh modeled impact
Higher input lowers the modeled result
Higher proceeds reduce the mathematical harvested loss.
Gains available to offsetHigh modeled impact
Higher input raises the modeled result
Entered gains cap the loss valued in the current scenario.
Effective tax rateHigh modeled impact
Higher input raises the modeled result
The rate scales the estimated value of the usable loss.
Implementation costsLow modeled impact
Higher input lowers the modeled result
Entered costs reduce the modeled net current benefit.
Impact ranks only the entered arithmetic. It does not determine tax eligibility, replacement-property treatment, or whether a loss is currently claimable.
Meaning
What this means
Meaning
The calculator estimates scenario math only. Whether a loss is deductible depends on jurisdiction, account type, replacement trades, and local superficial-loss or wash-sale rules.
Implication
A loss only has modeled current tax value to the extent it offsets the entered gains, and implementation costs can reduce that value. Tax treatment must be confirmed for the relevant jurisdiction and account.
Formula and methodology
How the calculator works
Harvested loss
max(adjusted cost basis + selling costs − sale proceeds, 0)Usable loss now
min(harvested loss, entered capital gains)Estimated current tax value
usable loss × effective tax rateEstimated net current benefit
estimated tax value − implementation costsThe estimator values only the portion matched against the gains you enter. It does not carry unused losses to other periods. Money is displayed to whole currency units after full-precision calculation.
Assumptions and limitations
What the scenario includes—and leaves out
Assumptions
- All money amounts use the same currency and tax period.
- The entered effective rate reasonably reflects the gain being offset.
- The transaction qualifies for the treatment assumed by the user.
Limitations
- Wash-sale, superficial-loss, replacement-property, holding-period, account-type, and carryforward rules vary by jurisdiction.
- Tax brackets, inclusion rates, state or provincial rules, and future tax value are not modeled.
- This is an educational estimate, not tax or legal advice; consult current local rules or a qualified professional.
Educational scenario only. Results are modeled estimates, not forecasts or personalized financial, investment, legal, or tax advice.
Known-answer checks
Examples used to validate the engine
Default caseA 50,000 basis sold for 40,000 creates a 10,000 loss; 8,000 is usable against entered gains.
Tax valueAn 8,000 usable loss at 25% has an estimated current tax value of 2,000.
No economic lossSale proceeds at or above basis plus selling costs produce a zero harvested loss.
Invalid valuesA non-positive basis, negative amounts, rates outside 0%–100%, and non-finite values are rejected.
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