Should I Pay Off Debt or Invest? This calculator will help determine whether you should invest funds or pay down debt. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Related Content How Stocks Work Understanding how a stock works is key to understanding your investments. What Is My Life Expectancy? Estimate how many years you may need retirement assets or how long to provide income to a surviving spouse or children. Eight Mistakes That Can Upend Your Retirement There are common mistakes you can avoid when saving for retirement.