Doubling Your Money This calculator demonstrates the power of compound interest. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Share | Related Content The Power of Compound Interest Learn how to harness the power of compound interest for your investments. Budget Check Up: Tax Time Is the Right Time Tax preparation may be the perfect time to give the household budget a check-up. Paying Off a Credit Card Enter various payment options and determine how long it may take to pay off a credit card.