What Is Compound Interest and Why It Matters

By Allen Krewzz

Published June 29, 2026Updated July 4, 2026

What Is Compound Interest?

The three ingredients

A Simple Worked Example

The single biggest lever in compounding is time, not the amount you start with. An extra ten years can matter more than a much larger contribution made later.

Why Time Is So Powerful

Compounding Frequency

The Rule of 72

Compounding Works Against You Too

How to Make Compounding Work for You

Conclusion

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