Compound Interest Calculator
See how money grows with compound interest, compounded monthly, quarterly or yearly, with optional monthly additions and a year-by-year table.
Runs in your browser. Nothing is uploaded.
About the Compound Interest Calculator
Compound interest is interest earned on earlier interest: each period the interest is added to the balance, so the next period's interest is a little larger. Over long periods this snowball effect is what turns regular saving into a large sum.
Enter a starting amount, an optional amount added every month, the yearly rate, the term and how often interest is added. The calculator shows the final value, how much of it is your money and how much is interest, and the balance at the end of every year. Compare monthly and yearly compounding, or a higher rate against a longer term, to see what matters most.
How to use the Compound Interest Calculator
- 1
Enter the starting amount and, if you save every month, the monthly addition.
- 2
Enter the yearly interest rate and the term in years or months.
- 3
Choose how often interest is added: monthly, quarterly, half-yearly or yearly.
- 4
Read the final value and the interest earned, and scroll the yearly table.
Examples
1,00,000 at 8% for 10 years, compounded yearlyInvested: ₹1,00,000.00
Interest earned: ₹1,15,892.50
Final value: ₹2,15,892.505,000 a month at 8% for 10 years, compounded monthlyInvested: ₹6,00,000.00
Interest earned: ₹3,20,828.38
Final value: ₹9,20,828.38Good to know
- Assumes a fixed rate for the whole term. Monthly additions are made at the start of each month.
- Tax and inflation are not taken into account.
Frequently asked questions
What is the compound interest formula?
A = P × (1 + r ÷ n)^(n × t), where P is the starting amount, r the yearly rate ÷ 100, n the number of times interest is added each year and t the number of years.
Does more frequent compounding make a big difference?
A little. At 8% a year, monthly compounding gives an effective 8.30% against 8% for yearly. The rate and the number of years matter far more.
What is the rule of 72?
A quick estimate: divide 72 by the yearly rate to get the years needed to double your money. At 8%, about 9 years.
Is anything I enter saved?
No. The calculation runs on your device and nothing is stored or sent anywhere.
Related tools
More tools that pair well with this one.