Adjusted taxable estate = taxable estate + lifetime taxable gifts (the unified gift and estate tax system).
Federal taxable amount = adjusted taxable estate − basic exclusion ($15M for 2026; $13.99M for 2025) − DSUE from a predeceased spouse if any.
Federal estate tax = graduated brackets from 18% on the first $10K of taxable amount up to 40% on amounts over $1M. Most taxable estates hit 40% quickly.
State estate tax = computed on the gross estate above the state-specific threshold. Cliff states (Massachusetts, Illinois, New York) tax the full estate when over threshold.
Disclaimer. This estimator is a planning tool for educational use, not a substitute for professional advice. Federal and state estate tax law is dense and full of exceptions (QTIP elections, generation-skipping transfer tax, qualified family-owned business deduction, special use valuation under §2032A, alternate valuation under §2032, etc.). The 2026 federal $15M exclusion reflects the TCJA-reset baseline and is scheduled to remain through 2034 unless Congress acts. Verify all thresholds with current authorities. Prepared by Sean C. Lucas, Esq., Delaware Bar — not legal advice.
What this tool replaces
The back-of-envelope multiplication that estate planners do at the beginning of every new client engagement, when the client asks "do I have an estate tax problem?" before they have any documents in hand.
For most clients in 2026, the answer is: no federal exposure (the $15M / $30M-married threshold is high), and no state exposure if domiciled in a no-tax state. The clients who do have a problem typically have multi-state exposure, a cliff-state domicile (MA, IL, NY), unused DSUE, or a large lifetime-gifts history that quietly consumed the exclusion.