Estate Tax Calculator

What Is an Estate Tax Calculator?

An Estate Tax Calculator is a financial planning tool that provides a simplified estimate of potential federal estate tax exposure at death. It starts with the gross estate, subtracts the deductions entered by the user, considers prior taxable gifts on a simplified basis, applies the federal exclusion amount used by the model, and estimates tax using the federal graduated transfer-tax rates.

This calculator is designed for U.S. federal estate tax planning. It is useful for exploring scenarios involving estate values, debts, charitable deductions, marital deductions, prior taxable gifts, and a potential deceased spousal unused exclusion amount (DSUE).

The result should be treated as an estimate rather than a tax return calculation. The actual federal estate tax computation uses additional rules and calculations that are not fully modeled here.

How the Estate Tax Calculator Works

The calculator uses a simplified planning sequence based on major concepts involved in federal estate tax calculations:

1. Start with the gross estate. Enter the estimated value of assets that may be included in the gross estate at death.
2. Subtract eligible deductions entered by the user. The calculator subtracts debts and allowable expenses, charitable deductions, and the marital deduction you enter.
3. Calculate the taxable estate. The result after these deductions is the taxable estate used by this simplified model.
4. Consider prior taxable gifts. The calculator adds the prior-taxable-gift amount you enter to the taxable estate as a simplified representation of cumulative transfers. Actual Form 706 treatment is more detailed and can involve gift tax payable and credits.
5. Apply the simplified federal exclusion. The model uses the 2026 federal basic exclusion amount of $15,000,000 and adds a DSUE amount only when the user selects Married or Surviving Spouse.
6. Estimate tax on the amount above the simplified exclusion. The calculator applies the federal graduated transfer-tax rate schedule to that amount to produce the planning estimate.

This sequence is intended to make the calculation transparent. It should not be interpreted as a line-by-line reproduction of IRS Form 706.

The Federal Estate Tax Exemption

For 2026, the federal basic exclusion amount is $15,000,000 per individual. Federal estate and gift tax rules can change over time, so the amount used by this calculator should be checked against current IRS guidance when the calculator is used for actual planning.

The federal exclusion is only one part of the estate tax calculation. Deductions, prior taxable gifts, DSUE, credits, gift tax payable, valuation issues, and other factors can affect the actual federal estate tax reported on Form 706.

Portability and the Deceased Spousal Unused Exclusion

Portability can allow a surviving spouse to use a deceased spouse’s unused federal exclusion amount. This unused amount is generally referred to as the Deceased Spousal Unused Exclusion (DSUE).

DSUE is not automatically available simply because someone is married. The deceased spouse’s estate generally must make a valid portability election, usually through Form 706, subject to the applicable filing deadline and any available late-election relief. If portability is not properly elected, the unused exclusion generally cannot be transferred to the surviving spouse.

This calculator lets the user enter a DSUE amount manually rather than automatically assuming that a married couple receives twice the individual exclusion.

State Estate and Inheritance Taxes

Some states and the District of Columbia impose separate estate taxes, while some states impose inheritance taxes. State rules, exemptions, rates, and filing requirements can differ substantially from federal rules.

This calculator estimates federal estate tax only. If the estate may be subject to a state estate or inheritance tax, a separate state-specific calculation should be performed using current state rules.

Key Inputs in the Estate Tax Calculator

Gross Estate Value

Gross estate value represents the estimated value of assets that may be included in the federal gross estate. Depending on the circumstances, this can include real estate, financial accounts, business interests, retirement assets, life insurance interests, vehicles, and personal property.

Debts and Allowable Expenses

Qualifying debts and certain estate expenses may be deductible under federal estate tax rules. The calculator lets you enter an estimated combined amount. Actual deductibility depends on the applicable rules and documentation.

Charitable Deductions

Qualifying charitable transfers may be deductible for federal estate tax purposes. The amount and eligibility of a deduction depend on the organization, property transferred, and applicable tax rules.

Marital Deduction

Qualifying property passing to a surviving spouse may qualify for the federal marital deduction. The unlimited marital deduction generally applies to qualifying transfers to a surviving U.S.-citizen spouse, while special rules can apply in other situations, including certain transfers to a non-U.S.-citizen spouse.

Prior Taxable Gifts

Prior taxable gifts can affect the federal estate and gift tax computation because the federal transfer-tax system considers cumulative transfers. This calculator includes a simplified prior-taxable-gifts input, but it does not reproduce all Form 706 calculations involving gift tax payable, credits, or other adjustments.

How to Use the Estate Tax Calculator Effectively

1. Estimate your current exposure. Enter your best estimate of the gross estate and relevant deductions.
2. Test charitable deductions. Adjust the charitable deduction to explore how qualifying charitable transfers may affect the simplified estimate.
3. Review marital planning. Enter qualifying marital deductions and, where applicable, a documented DSUE amount.
4. Account for prior gifts. Enter a reasonable estimate of prior taxable gifts if applicable, understanding that the calculator uses simplified treatment.
5. Consider state taxes separately. Federal results do not represent state estate or inheritance tax liability.
6. Revisit the calculation periodically. Asset values, tax rules, and estate-planning circumstances can change.

What the Estate Tax Calculator Does Not Include

• State estate and inheritance taxes. State-level death taxes are not included.
• Full Form 706 mechanics. The calculator does not reproduce the complete tentative-tax, unified-credit, gift-tax-payable, DSUE, and other Form 706 calculations.
• Valuation discounts. Closely held businesses, partnerships, and other assets may involve valuation issues that require professional appraisal and tax analysis.
• Generation-skipping transfer tax. GST tax is a separate transfer-tax system and is not calculated here.
• Life insurance ownership rules. Life insurance may be included in the gross estate depending on ownership and control. A policy held through an irrevocable life insurance trust may receive different treatment if the applicable requirements are satisfied.
• Complex trust structures. Trusts and advanced estate-planning arrangements can involve rules that are not represented by this simplified calculator.

The calculator is therefore best used as a planning and educational tool rather than as a substitute for Form 706 preparation or individualized tax advice.

Estate Tax Calculator vs Income Tax Calculator

An Estate Tax Calculator estimates potential transfer-tax exposure associated with an estate at death, while an income tax calculator estimates taxes associated with income during a tax year. They use different rules, thresholds, deductions, credits, and filing requirements.

When to Use the Estate Tax Calculator

• When your estate is approaching the federal exclusion amount and you want a preliminary estimate.
• When reviewing charitable planning and the potential effect of qualifying charitable deductions.
• After a spouse’s death when portability and DSUE may need to be considered.
• Before an estate-planning consultation so you can discuss approximate values and scenarios.
• When reviewing lifetime gifting and its potential effect on the federal transfer-tax calculation.
• When state tax exposure is relevant and a separate state calculation is needed.

Limitations of an Estate Tax Estimate

• Simplified calculation: The result is a planning estimate and not a reproduction of IRS Form 706.
• Current-law dependency: Tax thresholds and rules can change, so current IRS guidance should be checked before relying on the result.
• User inputs: The estimate is only as accurate as the values and deductions entered.
• State taxes: State estate and inheritance taxes are excluded.
• Complex tax rules: Gift tax, credits, trust structures, valuation rules, and other issues can materially affect actual liability.

This calculator is intended to provide a transparent starting point for understanding potential federal estate tax exposure and preparing for discussions with qualified estate-planning professionals.