What is the difference between simple and compound interest?


Simple interest and compound interest are two methods used to calculate interest on a principal amount over a specific period. Here are five key differences between simple interest and compound interest:

Calculation Method:

Simple Interest: Simple interest is calculated only on the original principal amount throughout the entire period. The interest remains constant over time, and there is no consideration of interest earned on previously earned interest.
Compound Interest: Compound interest takes into account not only the original principal amount but also the accumulated interest from previous periods. In other words, interest is calculated on both the principal and the accumulated interest.

Formula:

Simple Interest: Interest accrues linearly over time. The interest amount remains the same for each time period.
Compound Interest: Interest accrues exponentially. The interest for each period is calculated based on both the principal and the accumulated interest from previous periods, leading to a compounding effect.

Amount at Maturity:

Simple Interest: The total amount at maturity is calculated by adding the original principal and the total simple interest accrued over the specified period:

Use Cases:

Simple Interest: Simple interest is often used in scenarios where the interest is applied to a loan or investment over a short period, and the compounding effect is negligible. It is a straightforward method suitable for situations with fixed interest rates.
Compound Interest: Compound interest is more prevalent in long-term investments or loans where the interest compounds periodically. It is common in savings accounts, certificates of deposit, and other financial instruments where interest is reinvested.
In summary, the main distinction lies in how interest is calculated and accrued over time. Simple interest is linear and applies only to the original principal, while compound interest is exponential, taking into account both the principal and previously earned interest. Compound interest leads to a greater accumulation of interest over time compared to simple interest.