Self-Employed Retirement Plans Estimate the maximum contribution amount for a Self-Employed 401(k), SIMPLE IRA, or SEP. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Have A Question About This Topic? Name Email Address Question Thank you! Oops! Related Content Are You Prepared for an Estate Tax Sunset? The federal estate tax exemption sunsets in 2025. Learn more about what to do to make the most of the higher threshold. Understanding Marginal Income Tax Brackets An inside look at how marginal income tax brackets work. Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates.