Compound Interest Calculator

See how your money grows over time with compound interest — and compare different compounding frequencies.

Let your money grow on its growth.

Principal Amount

Interest Rate (% p.a.)

Compounding Frequency

Time Period

years

Total Amount

Principal

—

Interest Earned

—

More frequent compounding (monthly vs yearly) grows your money faster for the same rate.

What is compound interest?

Compound interest is interest calculated on both your original principal and the interest it has already earned — unlike simple interest, which only ever applies to the original amount. That's why compound interest grows faster the longer money stays invested: each period's interest starts earning its own interest too.

Compound interest formula

Where n is how many times a year interest compounds and t is the time period in years.

Formula

A = P(1 + r

n)ⁿᵗ

WhereA = final amount, P = principal, r = annual rate, n = compounds per year, t = years

Worked Example — ₹2,000 for 2 years at 5% (annual compounding)

Principal₹2,000.00Rate5% p.a.Time2 years

↓Total Amount = ₹2,205.00Interest earned ₹205.00

Common Mistakes to Avoid

This models 4 fixed frequencies, not daily compounding. Monthly, quarterly, half-yearly, and annually are supported — there's no daily option, so "daily compound interest" queries won't match what this calculator computes.
More frequent compounding means faster growth, but the effect is small. Monthly vs. yearly compounding at the same rate only changes the result by a small amount — the rate and time period matter far more than the frequency.
This doesn't model withdrawals or continuous compounding. It assumes the full amount stays invested for the whole period, compounding at one of the four standard frequencies — not the continuous (e^rt) limit case.