Comprehensive Guide
Learn more in our Business & Tax Guide.
How it works
tax-loss harvesting calculator — general takes your inputs and produces gains offset by losses, tax savings from harvesting, remaining losses (carry forward), watch for wash sale rule. Calculate the tax savings from selling losing investments to offset gains — the annual tax-loss harvesting opportunity. You provide 4 inputs: Realized capital gains this year (currency, in dollars) (default: 10000 dollars); Available investment losses (currency, in dollars) (default: 8000 dollars); Capital gains tax rate (%) (percent, in percent) (default: 15 percent); Ordinary income tax rate (%) (percent, in percent) (default: 22 percent). The calculator returns 4 outputs: Gains offset by losses (the primary result); Tax savings from harvesting (a secondary output); Remaining losses (carry forward) (a secondary output); Watch for wash sale rule (a supplementary figure). Business tax and finance calculations combine multiple moving parts — revenue, expenses, depreciation, tax brackets, and timing — in ways that make back-of-envelope estimates unreliable. This calculator handles the interaction of those variables precisely, so your business decisions rest on real arithmetic. The underlying formula: Tax savings = Losses used × Capital gains tax rate. Remaining losses carry forward. With the default values, gains offset by losses is computed from the interaction of every input field — change any one of them and the result updates immediately, so you can stress-test different scenarios without re-entering the whole form. Adjust the inputs to match your real financial situation. The defaults are realistic starting points, but every person's circumstances differ — your actual income, expenses, rates, and timelines will produce a different answer. Use the tool iteratively: start with the defaults, then change one variable at a time to see which factor has the largest impact on your outcome.Formula
Tax savings = Losses used × Capital gains tax rate. Remaining losses carry forward.
Tips
- Harvest losses before year-end — you must realize them by December 31.
- Avoid wash sale violations: do not buy the same investment within 30 days.
- Buy a similar (not identical) fund to maintain market exposure while waiting.
- You can deduct up to $3,000/year in losses against ordinary income.
Frequently asked questions
What is the wash sale rule?
You cannot deduct a loss if you buy the same or substantially identical investment within 30 days before or after the sale. Workaround: sell a losing stock, immediately buy a similar stock from a different company, wait 31 days, then buy back the original if desired.
How much can I deduct in investment losses?
Against capital gains: unlimited. Against ordinary income: $3,000/year ($1,500 if married filing separately). Excess losses carry forward indefinitely to future tax years.
How accurate are the calculator results?
The math is exact — the same formulas a financial professional would use by hand. The precision of the output depends entirely on how realistic your inputs are. Use your actual numbers rather than estimates when possible. The defaults are reasonable starting points, but your real income, rates, and timeline will produce a different result.