Enter a principal, a yearly interest rate and the time to see the amount with compound interest, how much more it is than simple interest, and the balance at the end of each year. Choose yearly, half-yearly, quarterly, monthly or daily compounding; part years work too.
How to use Compound Interest Calculator
Enter the principal: the amount you start with.
Enter the yearly interest rate and the time in years (2.5 for two and a half years).
Choose how often interest is compounded.
Read the amount, the interest, the comparison with simple interest, the formula with your numbers and the yearly table.
Frequently asked questions
What is the compound interest formula?
A = P × (1 + r ÷ n)^(n × t), where P is the principal, r the yearly rate as a decimal, n how many times a year interest is added and t the time in years. Compound interest is A − P. ₹1,00,000 at 10% compounded yearly for 2 years gives ₹1,21,000.
How is it different from simple interest?
Simple interest is earned only on the principal: P × r × t. Compound interest is also earned on interest already added, so it grows faster the longer the time. The calculator shows both so you can see the gap.
Does compounding more often make a big difference?
A little. At 10% for 1 year, yearly compounding gives 10% interest, quarterly about 10.38% and daily about 10.52%. Over long periods the gap grows, but the rate and the time matter far more.
Can I use it for CBSE or competitive exam questions?
Yes. Choose the compounding that the question states (half-yearly means 2 times a year, quarterly 4) and enter part years as decimals. The formula line shows the working with your numbers.
₹1 lakh at 10% for 1 year
Compounded
Amount
Interest
Yearly
₹1,10,000
₹10,000
Half-yearly
₹1,10,250
₹10,250
Quarterly
₹1,10,381
₹10,381
Monthly
₹1,10,471
₹10,471
Daily
₹1,10,516
₹10,516
Calculators built on the same idea
A bank deposit is compound interest with quarterly compounding: see the FD calculator. For regular monthly investing use the SIP calculator, and for yearly deposits the PPF calculator. For a one-off percentage, the percentage calculator shows its formula too.