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 Estimate Your RMD Help determine the required minimum distribution from an IRA or other qualified retirement plan. Choosing a Business Structure Entrepreneurs all face the same question, “Which business structure should I adopt?” Contributing to an IRA? Determine if you are eligible to contribute to a traditional or Roth IRA.