Retirement readiness involves more than just the money. What do you want your life to look like after you retire? Do you imagine yourself on a boat, sailing with the breeze on Lake Michigan? Will you stay where you are, or relocate to a warmer climate? Take a road trip across the country? Maybe you'll volunteer for a local organization, start your own business, or immerse yourself in your favorite hobby.

What about health care? Are you prepared to handle unexpected changes, or taking care of a loved one?

Think about all of the things that will give your life meaning after you retire, and then estimate your financial needs to make them happen.

A successful retirement is like a three-legged stool. You can't depend on just your employer-sponsored plan any more than you can rely solely on savings and investments or social security for financial security in your later years. To offer the best chance for success, you need all three.

Estimate what each of the three legs will be, and subtract how much you think you'll need per month in retirement. If there's a gap, consider how you'll close it. Maybe you'll even add a fourth leg to that stool by working part-time or full-time after you retire.