What's My Potential Estate Tax? This calculator helps estimate your federal estate tax liability. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Share | Related Content When Do You Need a Will? When do you need a will? The answer is easy: Right Now. And the Executor Is The right executor may help ensure the distribution of your assets is done with as little upheaval as possible. Principles of Preserving Wealth How federal estate taxes work, plus estate management documents and tactics.