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 Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates. 9 Facts About Social Security There are things about Social Security that might surprise you. Saving Early & Letting Time Work For You The earlier you start pursuing financial goals, the better your outcome may be.