Interest Calculator

Calculate simple and compound interest.

Currency:
Interest Calculator
%
Yrs
Compound Interest
Simple Interest
Compound Interest
Extra via Compounding

Calculate simple and compound interest for savings, loans, and investments with fast, transparent math that works in India and globally.

Simple vs compound interest

Simple interest is calculated only on principal, while compound interest is calculated on principal plus accumulated interest.

Interest formulas

Simple Interest = P x R x T; Compound Amount = P x (1 + r/n)^(n x t)

Use compound mode for most modern investments and many deposit products.

Where this calculator is useful

  • FD and savings planning
  • Education and goal-based investments
  • Loan repayment estimation
  • Comparing compounding frequencies

How to calculate interest quickly

  1. Choose simple or compound mode
  2. Enter principal, rate, and time period
  3. Set compounding frequency if needed
  4. View total amount and interest earned/paid
  5. Compare alternate rates or tenures

Compound interest example

Scenario: Invest Rs 2,00,000 at 9% annually for 5 years, compounded yearly.

Inputs

  • P = 2,00,000
  • r = 9%
  • t = 5
  • n = 1

Calculation

  • Amount = 2,00,000 x (1.09)^5 ≈ Rs 3,07,724
  • Interest earned ≈ Rs 1,07,724

Result: Investment grows to roughly Rs 3.08 lakh in 5 years.

Frequently Asked Questions

For wealth creation, compound interest is usually better over long periods.

More frequent compounding can slightly increase final maturity amount.

Yes, though reducing-balance EMI loans need dedicated amortization logic for precision.

Effective annual rate is better for comparing products with different compounding frequency.