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 Charitable Giving: Smart from the Heart Do you have causes that you want to support with donations? How Will Working Affect Social Security Benefits? Knowing the rules may help you decide when to start benefits. Red Flags for Tax Auditors Here are six flags that may make your tax return prime for an IRS audit.