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 Bi-Weekly Payments This calculator estimates the savings from paying a mortgage bi-weekly instead of monthly. Breaking Down the Parts of Medicare Medicare is broken down into four specific parts—but what do they mean? This article will help you understand each piece. Retirement Plan Detectives A couple become Retirement Plan Detectives, searching records from old employers.