Compound Interest Calculator
Calculate compound interest on a lump sum plus monthly SIP contributions.
Last updated: August 2026
Add a fixed amount saved every month to see the combined growth.
Maturity value
₹1,96,715
After 10 year(s)
Total interest earned
₹96,715
Interest + growth on investments
Total invested
₹1,00,000
Your principal only
Your money grows by
96.7%
Gain over the total invested
How it works
A = P × (1 + r/n)^(n×t). SIP adds the future value of each monthly contribution.
Example: ₹1,00,000 at 7% yearly for 10 years → ₹1,96,715.
Frequently Asked Questions
What is compound interest?
Compound interest is interest earned on both your original principal and the interest already added to it. Over time your money grows faster because each period's interest is calculated on a larger balance.
How is compound interest calculated?
The formula is A = P × (1 + r/n)^(n×t), where P is the principal, r is the annual rate as a decimal, n is the number of compounding periods per year and t is the time in years.
What is the difference between simple and compound interest?
Simple interest is only ever calculated on the original principal, so it grows linearly. Compound interest also earns interest on the interest, so the balance grows faster the longer it stays invested.
Why does compounding more frequently give higher returns?
The more often interest is added to your balance, the sooner it starts earning its own interest. Monthly compounding therefore returns slightly more than yearly compounding at the same nominal rate.
Can I use this for SIP and FD planning?
Yes. For a lump-sum fixed deposit, keep the monthly contribution at 0. For SIP planning, add a monthly amount to see the combined growth of a lump sum plus regular investments.
Does this account for tax on interest?
No. The result is the gross pre-tax value. Interest on fixed deposits is taxable at your slab rate, while equity mutual funds have their own capital-gains rules. Treat the output as a pre-tax estimate.