My Retirement Savings Estimate how long your retirement savings may last using various monthly cash flow rates. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Share | Have A Question About This Topic? Name Email Address Message Thank you! Oops! Related Content 18 Years’ Worth of Days The average retirement lasts for 18 years, with many lasting even longer. Will you fill your post-retirement days with purpose? The 12 Steps to Living Confidently: Savings and Cash Flow Why is Cash Flow so important to understand? How Interest Rates Affect Everything This is a good infographic to use, and reuse, whenever the benchmark interest rate goes up.