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 Can I Refinance My Mortgage? This calculator can help determine whether it makes sense to refinance your mortgage. How Compound Interest Works Use this calculator to better see the potential impact of compound interest on an asset. Do You Owe The AMT? If you want to avoid potential surprises at tax time, it may make sense to know where you stand when it comes to the AMT.