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 What Is a Roth 401(k)? Roth 401(k) plans combine features of traditional 401(k) plans with those of a Roth IRA. Finding the Balance The sandwich generation faces unique challenges. For many, meeting needs is a matter of finding a balance. Find That Lost Retirement Account With over 24 million “forgotten” 401(k) accounts, you may be surprised to learn of your unclaimed “found” money.