Estate Tax Calculator
Estimate your 2026 U.S. federal estate tax liability from your gross estate value and available federal exclusion. Federal only — this is an estimate, not tax or legal advice.
How It's Calculated
Formula
\text{Taxable Amount} = \max(0, \text{Gross Estate} - \text{Available Exclusion}) \qquad T(x) = \sum_{\text{brackets}} \text{rate}_i \times \text{amount in bracket}_i \qquad \text{Federal Estate Tax} = \max(0,\; T(\text{Gross Estate}) - T(\text{Available Exclusion}))This calculator estimates your 2026 U.S. federal estate tax liability using the same tentative-tax-minus-applicable-credit mechanic as IRS Form 706. First it computes a tentative tax by running your full gross estate through the federal unified transfer-tax rate schedule (26 U.S.C. §2001(c)), which is progressive from 18% up to a 40% top rate on amounts above $1,000,000. It computes that same tentative-tax function again on your available exclusion — which defaults to the 2026 basic exclusion amount ($15,000,000) under IRC §2010(c)(3) but is editable — giving an applicable-credit-equivalent amount. Subtracting the credit-equivalent from the tentative tax on the full estate (floored at $0) gives the estimated federal estate tax. This mirrors the real Form 706 mechanic more closely than simply running the schedule against (gross estate − exclusion) starting over at $0: the exclusion works as a CREDIT against tax computed on the whole estate, not as a reset of the progressive schedule, so the portion of your estate above the exclusion is taxed at the rate your estate's actual size reaches — never at the schedule's low bottom brackets just because the excess itself happens to be small. "Taxable Amount" (gross estate minus available exclusion) is still reported for reference, but note it is not what the tax rate schedule is applied to directly. This is a simplified V1 estimate: it does NOT model the marital deduction, the charitable deduction, portability of a deceased spouse's unused exclusion (DSUE), reconstruction of a full gift-tax return history, generation-skipping transfer tax, or any state estate or inheritance tax — all of which can materially change actual estate tax liability. Married couples' exclusion does not automatically double here; you should enter the exclusion actually available to your estate. This is an estimate for general planning purposes, not tax or legal advice — consult a qualified estate planning professional for your actual situation.
Worked Examples
Below the 2026 exclusion: $10,000,000 gross estate, default exclusion
- Available exclusion defaults to $15,000,000.
- Gross estate ($10,000,000) is below the available exclusion, so the taxable amount is floored at $0 and the tentative tax on the estate is less than the credit-equivalent on the exclusion.
- Estimated federal estate tax = $0.
Above the 2026 exclusion: $20,000,000 gross estate, default exclusion
- Tentative tax on the full $20,000,000 estate: $345,800 base through $1,000,000, plus 40% of the remaining $19,000,000 = $7,600,000, for $7,945,800 total.
- Applicable-credit-equivalent tax on the $15,000,000 exclusion: $345,800 base plus 40% of the remaining $14,000,000 = $5,600,000, for $5,945,800 total.
- Estimated federal estate tax = $7,945,800 − $5,945,800 = $2,000,000.
- (Taxable amount, reported for reference, is $20,000,000 − $15,000,000 = $5,000,000 — but note the tax above is NOT simply that figure walked through the schedule from $0.)
Reduced exclusion from prior taxable gifts: $20,000,000 gross estate, $5,000,000 available exclusion
- Tentative tax on the full $20,000,000 estate = $7,945,800 (as above).
- Applicable-credit-equivalent tax on the $5,000,000 exclusion: $345,800 base plus 40% of the remaining $4,000,000 = $1,600,000, for $1,945,800 total.
- Estimated federal estate tax = $7,945,800 − $1,945,800 = $6,000,000.
Frequently Asked Questions
Why is this calculator federal only?
This V1 estimates federal estate tax exclusively. Some states levy their own separate state estate or inheritance tax on top of the federal amount, with their own exclusion thresholds and rates that vary significantly by state — modeling those is out of scope for this calculator, and no state figure is estimated or implied here.
What is the "available exclusion" and why would I lower it?
The available exclusion used for this simplified estimate defaults to the full 2026 federal basic exclusion amount ($15,000,000). Prior taxable gifts and portability can affect the actual applicable credit; this calculator does not reconstruct gift-tax history. If you know your remaining available exclusion is lower — for example, because of lifetime taxable gifts tracked via IRS Form 709 — you can enter that reduced amount directly.
Does the exclusion automatically double for married couples?
No. A surviving spouse can potentially use their deceased spouse's unused exclusion through a portability election (DSUE), but that requires a timely election on an estate tax return and is not automatic. This calculator does not compute portability — if you're married, enter the exclusion amount actually available to your estate under your specific circumstances.
What isn't included in this estimate?
This V1 does not model the marital deduction (transfers to a surviving spouse are typically unlimited and untaxed), the charitable deduction, portability/DSUE, generation-skipping transfer tax, or any state estate or inheritance tax. Each of these can substantially reduce — or in the case of state taxes, add to — actual estate tax liability. This is a simplified estimate for general planning purposes, not a substitute for professional estate tax or legal advice.
How is the tax actually calculated once I'm above the exclusion?
This calculator does NOT simply run the amount above your exclusion through the rate schedule starting at $0 — that would tax a small excess at the schedule's low bottom brackets even for a very large estate, which isn't how the real applicable-credit mechanism works. Instead, it runs your FULL gross estate through the federal unified transfer-tax rate schedule (26 U.S.C. §2001(c)) — progressive from 18% up to a 40% top marginal rate on amounts above $1,000,000 — to get a tentative tax, runs that same schedule on your available exclusion to get a credit-equivalent amount, and subtracts the credit-equivalent from the tentative tax. That way, the portion of your estate above the exclusion is taxed at the marginal rate your estate's actual size reaches, matching how the IRS Form 706 tentative-tax-minus-applicable-credit mechanism behaves.