Compound Interest Calculator

Calculate compound interest with any compounding frequency — yearly, half-yearly, quarterly, monthly.

₹1,000₹1,00,00,000
% p.a.
120
yr
140
Maturity amount
₹1,48,595
Principal
₹1,00,000
Compound interest
₹48,595
Principal vs interest
Principal67%
Interest33%

About the Compound Interest Calculator

Compound interest is interest earned on both your principal and the interest already accumulated — the engine behind every long-term investment. The AlarmDaddy Compound Interest Calculator computes the maturity value and total interest for any principal, rate, tenure, and compounding frequency.

Enter the principal, the annual rate, the tenure, and choose how often interest compounds (annually, half-yearly, quarterly, monthly, or daily). The calculator shows the final amount and the interest component. Compare it side by side with simple interest to see exactly how much extra compounding earns over time — the gap widens dramatically as the tenure grows.

How to use this calculator

  1. 1Enter the principal amount.
  2. 2Enter the annual interest rate.
  3. 3Enter the time period in years.
  4. 4Choose the compounding frequency.
  5. 5Read the maturity amount and total compound interest.

The formula

A = P × (1 + r/m)^(m × t)

Where P is the principal, r is the annual rate (decimal), m is the number of compounding periods per year, and t is the time in years. Higher m (more frequent compounding) produces a slightly larger maturity value.

Frequently asked questions

Simple interest is calculated only on the original principal. Compound interest is calculated on the principal plus all previously earned interest, so it grows faster over time.