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 Message Thank you! Oops! Related Content Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates. Creative Ways to Motivate Your Employees Five creative (and inexpensive) ideas for motivating your employees. Comparing Investments This calculator compares the net gain of a taxable investment versus a tax-favored one.