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 | Have A Question About This Topic? Name Email Address Question Thank you! Oops! Related Contents The Power of Compound Interest Learn how to harness the power of compound interest for your investments. How Big is Money? Learn a little about worldwide currency in this fun infographic Paying Off a Credit Card Enter various payment options and determine how long it may take to pay off a credit card.