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 Red Flags for Tax Auditors Here are six flags that may make your tax return prime for an IRS audit. Comparing Mortgage Terms Estimate the total cost in today's dollars of various mortgage alternatives. All Muni Bonds Are Not Created Equal Gaining a better understanding of municipal bonds makes more sense than ever.