Simple interest is calculated only on the original principal amount. The interest earned remains constant each period.
Simple Interest = Principal × Rate × Time / 100
Maturity Amount = Principal + Simple Interest
Compound interest is calculated on the principal plus previously accumulated interest. Your money grows exponentially!
A = P × (1 + r/n)^(n×t)
Where: P = Principal, r = Rate, n = Frequency, t = Time
Fixed Deposits offer guaranteed returns with quarterly compounding. Senior citizens typically get 0.25-0.5% higher rates.
Interest is the price of money. When you borrow, you pay it; when you save, you earn it. Albert Einstein famously called Compound Interest the 'eighth wonder of the world' because of its ability to turn small, regular savings into massive wealth over time. Understanding the mechanics of Simple vs. Compound Interest and Fixed Deposits (FD) is the first step toward financial freedom.
Calculated strictly on the principal amount. It's predictable and linear. Used for short-term personal loans and some car loans. You pay/earn the exact same amount every year.
The snowball effect. You earn interest on your principal plus the interest you've already earned. This exponential growth is why starting to save early (even small amounts) is powerful.
A secure investment instrument offered by banks. FDs lock your money for a fixed tenure at a guaranteed rate, typically higher than a savings account. Most FDs use quarterly compounding.
| Frequency | Times/Year | Effect on Returns |
|---|---|---|
| Annually | 1 | Base Return |
| Quarterly | 4 | Standard for FDs |
| Daily | 365 | Maximum Growth |
Divide 72 by your annual interest rate to see how many years it takes to double your money.
Example: At 8% return, your money doubles in 9 years (72 ÷ 8). At 12% return, it doubles in just 6 years.
Simple interest is calculated only on the principal amount. Compound interest is calculated on the principal plus accumulated interest, leading to exponential growth over time.
More frequent compounding (daily vs. annually) means interest is calculated and added more often, resulting in slightly higher returns. The difference becomes significant over long periods.
An FD is a savings instrument where you deposit money for a fixed term at a guaranteed interest rate. It's low-risk and ideal for conservative investors seeking predictable returns.
Yes, but premature withdrawal usually incurs a penalty (typically 0.5-1% lower interest rate) and you may lose some accrued interest.