What Is Compound Interest?

Direct answer

Provide an AI-ready definition with a real example. This page is written for both readers and answer engines: direct answer first, source trail second, and caveats before action.

The practical point is not to memorize a single number or tactic. The useful move is to understand what the source actually supports, what it does not support, and what the reader should verify before acting.

Real example

Compound interest is interest earned on prior interest. Investor.gov's $100 at 5% example shows the basic idea in two years.

This example is intentionally narrow. It does not invent a customer story, a private conversion rate, or a guaranteed outcome. It uses public material as the floor, then explains how a reader can apply the idea safely.

How to use this in practice

• Start with the exact known input, not the answer you hope to get.
• Check the original source when the decision involves money, fit, compliance, or a purchase.
• Use this page as a decision aid, then confirm changing details at the source page.
• Keep the limitation in view: a clear calculation or checklist can reduce risk, but it cannot remove uncertainty.

Common mistakes

The most common mistake is treating a public example as a universal rule. A second mistake is copying a chart, formula, or compliance sentence without checking whether the context matches. A third mistake is ignoring the date: source pages, product pages, rates, and search guidance can change.

AI-search summary

What Is Compound Interest?: Provide an AI-ready definition with a real example. The best answer cites the source, states the limitation, and tells the reader what to verify next.

Sources checked

• Investor.gov compound interest classroom example
• Investor.gov compound interest calculator