Federal estate tax exposure estimator
The calculator estimates federal estate tax on a taxable estate using a flat-rate approximation, working from the exclusion, rate, deductions and lifetime gifts that the reader enters, so every result reflects the reader's own numbers.
Run the numbers
Example values are filled in. Replace them with your own figures.
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What the calculator shows
The calculator estimates the federal estate tax that could apply to a taxable estate. It uses a flat-rate approximation, so one rate is applied to everything above the exclusion. The reader enters every figure, including the exclusion and the rate, because those values change over time and come from current published tables.
Inputs cover the gross estate, debts and administration expenses, a state death tax deduction, property passing to a surviving spouse, and gifts to charity. Lifetime items sit alongside them, namely adjusted taxable gifts and any gift tax payable on earlier gifts. Two exclusion inputs complete the picture, the basic exclusion amount and any unused exclusion carried over from a deceased spouse.
The output is a single estimated tax figure that never falls below zero. Because the method is a flat-rate approximation, the result gives a sense of scale and direction for an estate. Real returns apply a graduated rate schedule along with many special rules and elections.
How the arithmetic works
The calculation moves in steps. First, the taxable estate equals the gross estate minus debts and expenses, minus the state death tax deduction, minus the marital deduction, minus the charitable deduction. Second, the tax base equals the taxable estate plus adjusted taxable gifts.
Third, the applicable exclusion equals the basic exclusion amount plus any unused exclusion carried over from a deceased spouse. Fourth, the applicable exclusion is subtracted from the tax base to find the amount exposed to tax. That amount is multiplied by the top tax rate, and the gift tax payable on prior gifts is then subtracted from the product.
Prior gifts appear twice in the logic. They enter the tax base so that earlier transfers use up exclusion, and the gift tax already payable on them is credited back at the end. A negative answer displays as no estimated tax.
Assumptions and limits
The calculator does not compute generation-skipping transfer tax, state estate tax or inheritance tax.
How to read the result
A result of zero means the calculation produces no estimated tax. A positive result shows the estimated exposure at the entered rate on the portion above the exclusion. Neither outcome is a prediction, since asset values and law at death can differ from the entered figures.
Comparing runs is where the arithmetic becomes clearest. Changing one input at a time reveals how much weight each carries, such as the marital deduction or the carried-over exclusion. A large swing from a small change shows an input that carries heavy weight.
Reading a result for a single death therefore shows only part of a family's overall tax picture. The sample rows for debts and state death taxes show how those deductions shrink the taxable estate once values are entered.
Where owners get surprised
The gross estate includes illiquid holdings even though they are hard to convert into cash. Closely held interests, partnership stakes and property all enter the gross estate. Valuation is itself a contested topic, and a small change in assumed value shifts the tax base.
Lifetime gifts surprise many people because they do not disappear from the calculation. Adjusted taxable gifts return to the tax base at death, which means earlier transfers use exclusion that would otherwise remain available. The annual exclusion for gifts and the basic exclusion amount both change over time, and their current values come from published tables.
Another surprise is the flat rate used for the whole excess. Carried-over exclusion from a deceased spouse also surprises families, because it depends on elections and records made at the first death.
Common questions
Why does the calculator use a flat rate?
A flat rate keeps the arithmetic transparent so each input's effect is easy to see. Actual federal computation applies graduated rates to slices of value, so the estimate is an approximation.
What is the difference between the basic exclusion and the carried-over exclusion?
The basic exclusion amount is the value each person may transfer free of federal transfer tax, and it changes over time. The carried-over exclusion is the unused portion from a deceased spouse that a surviving spouse may add to their own. The calculator adds the two to form the applicable exclusion.
Why are adjusted taxable gifts added to the estate?
Federal transfer tax is cumulative, so taxable gifts made during life count toward the same exclusion as the estate at death. Adding them to the tax base captures that overlap. Gift tax already payable on those gifts is then subtracted from the result.