What is Compound Interest? Formula, Meaning & Examples

Compound Interest is the interest calculated on the initial principal and also on the accumulated interest from previous periods. In simple terms, it is interest on interest, which helps your money grow faster over time.

Simple Definition

Compound interest is the interest earned on both the principal amount and previously earned interest.

Compound Interest Formula

The standard formula is:

A = P (1 + r/n)nt
  • A = Final Amount
  • P = Principal (initial investment)
  • r = Annual interest rate (decimal)
  • n = Number of times interest is compounded per year
  • t = Time (in years)

How Compound Interest Works

  1. You invest a principal amount
  2. Interest is added at regular intervals
  3. Next interest is calculated on total (principal + interest)
  4. This process repeats, increasing growth

Example

Principal: ₹10,000

Rate: 10% per year

Time: 2 years

  • Year 1: 10,000 × 10% = 1,000 → Total = 11,000
  • Year 2: 11,000 × 10% = 1,100 → Total = 12,100
  • Final Amount = ₹12,100

Compound Interest vs Simple Interest

Feature Compound Interest Simple Interest
Interest On Principal + Interest Principal only
Growth Faster Slower
Best For Investments Short-term loans

Why Compound Interest is Powerful

  • Helps money grow exponentially
  • Great for long-term investments
  • Used in savings accounts, FD, mutual funds
  • Encourages early investing

Use Compound Interest Calculator

Instead of manual calculation, use our tool for quick and accurate results:

Conclusion

Compound interest is a powerful concept that helps your money grow over time. The earlier you start investing, the more benefit you gain from compounding.

About this Calculator

Learn what compound interest is, how it works, its formula, and examples. Understand how your money grows with compounding.

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