Compound interest calculator

See how an investment grows with compound interest, given principal, rate, years, and compounding frequency.

Principal Annual rate (%) Years Compounds per year

Formula and algorithm

A = P × (1 + r/n)^(n×t)
P = principal, r = annual rate ÷ 100, n = compounding times per year, t = years.
Compound interest = A − P.

Input: ₹10,000 at 8% for 5 years, quarterly

Output: ≈ ₹14,859.47

Interest earned ≈ ₹4,859.47.

Input: Same at annual compounding

Output: ₹14,693.28

₹10,000 × 1.08^5 = ₹14,693.28.

Input: ₹10,000 at 8% for 5 years

Output: ≈ ₹4,859 interest

Compounding beats simple interest (₹4,000) over the same period.

What does compounding frequency change?

More frequent compounding (monthly vs annually) earns slightly more because interest itself earns interest sooner.

How is this different from simple interest?

Simple interest is only on the principal; compound interest also earns on accumulated interest.

Can I use it for an FD or savings account?

Yes — set the rate, years, and compounding frequency your bank uses (often quarterly).

Updated: June 7, 2026