The earlier you start saving for retirement, the more compound growth does the heavy lifting for you — which is exactly why this calculator focuses on how your current savings and monthly contributions grow over time rather than just how much you put in. Enter your current age, your target retirement age, what you have saved so far, how much you contribute monthly, and an expected annual return, and you will see your projected retirement corpus along with a breakdown of how much of that total came from your own contributions versus investment growth. It is a useful way to test how increasing your monthly contribution today, even by a small amount, can meaningfully change your final number decades from now.