Compound Interest Calculator
Calculate compound interest easily. Free online compound interest calculator — enter principal, rate, time and compounding frequency.
How to Use
- Enter the principal amount (your initial investment or deposit).
- Set the annual interest rate and the time period in years.
- Select compounding frequency — results update instantly as you adjust sliders.
Formula
A = P × (1 + r/n)^(n×t)
Compound Interest (CI) = A − P
Where: P = Principal | r = Annual Rate (decimal) | n = Compounding per year | t = Time in years
Example Calculation
Example: ₹10,000 at 8% p.a. compounded quarterly for 5 years
| Parameter | Value |
|---|---|
| Principal (P) | ₹10,000 |
| Rate (r) | 8% = 0.08 |
| Time (t) | 5 years |
| Frequency (n) | 4 (quarterly) |
| Total Amount (A) | ₹14,859 |
| Compound Interest | ₹4,859 |
Frequently Asked Questions
Compound interest is interest calculated on the initial principal AND the accumulated interest from previous periods. It grows exponentially, unlike simple interest which grows linearly.
Simple Interest = P×r×t. Compound interest applies the rate to a growing amount each period, resulting in significantly higher returns over time.
Divide 72 by the annual interest rate to estimate how many years it takes to double your money. At 8% p.a., money doubles in 72÷8 = 9 years.
Yes. More frequent compounding (daily vs annually) results in slightly higher returns. Daily compounding at 8% gives ~8.33% effective annual rate.
EAR = (1 + r/n)ⁿ − 1. It represents the actual annual rate when compounding occurs more than once per year.