Guide

Simple Interest vs Compound Interest

Understand the difference between simple and compound interest.

Quick answer

Simple interest is calculated only on principal. Compound interest adds interest to the balance, so future interest grows faster.

Step-by-step

Write down the values you already know.
Use the correct formula and keep the units consistent.
Calculate the result and check whether it makes practical sense.

Use the calculator

The easiest way to avoid mistakes is to use the related calculator and then review the formula shown on the page.

Open Interest Calculator →

Common mistakes

Using the wrong unit or percentage format.
Rounding too early.
Forgetting extra costs, waste, taxes, or allowances where they apply.

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