Compound interest can help turbocharge your savings and investments, or it can quickly lead to an unruly balance, keeping you stuck in a cycle of debt. Its magic can help you earn more — or owe more.

CNBC Select defines compound interest, how it works and ways to take advantage of it if you're looking for a new credit card ...

Our compound interest calculator is simple to use. All you need to do is fill in the following fields: Initial deposit: The amount of money you currently have saved and will use to fund your account.