Convert an annual interest rate into its monthly equivalent.
Simple division by 12.
Monthly rate: Annual rate ÷ 12
The monthly interest rate calculator divides an annual rate by 12 to give the rate that applies each month. It is the first step inside every EMI, SIP and recurring deposit calculation, because payments happen monthly while rates are quoted per year.
People use it to see how much interest a month adds to a loan balance, or how much a deposit earns in a month. If your home loan is at 9% a year, one month's interest is 0.75% of the outstanding balance. On a balance of ₹30 lakh, that is ₹22,500 for the month, which explains why early EMIs are mostly interest.
Knowing the monthly rate also helps you read a loan statement or check whether a bank has charged the right amount of interest in a given month.
1. Note the annual interest rate, for example 9%.
2. Divide by 12: monthly rate = annual rate ÷ 12, giving 0.75% for 9%.
3. For use in formulas, convert it to a decimal by dividing by 100: 0.0075.
4. To find one month's interest, multiply the balance by the decimal monthly rate.
5. If you need the monthly rate that compounds to an effective annual rate, compute (1 + annual rate ÷ 100)^(1/12) − 1 instead.
Loan agreements in India state an annual rate, and the monthly rate used for EMIs is that figure divided by 12. So a 9% loan charges exactly 0.75% a month on the outstanding balance. This is a convention, not a law of mathematics. It defines the annual figure as the nominal rate compounded monthly. The EMI formula on this site, and the one banks use, relies on this same division, which is why this simple calculator matches the monthly rate inside those tools.
A different question is: what monthly rate, compounded twelve times, gives exactly 9% over a year? The answer is 1.09^(1/12) − 1, about 0.7207%, a little less than 0.75%. Compounding 0.75% monthly gives about 9.38% a year instead. Mutual fund returns and CAGR figures are effective annual rates, so if you convert them to monthly rates by dividing by 12, a projection will slightly overstate growth. For loan EMIs, the divide-by-12 method is correct because that is how lenders define the rate.
Dividing by 12 treats every month as one-twelfth of a year. Some lenders compute interest on the actual number of days in each month, using a daily rate. Then February carries slightly less interest than March, and statements do not match a clean monthly calculation. The difference is small, a few rupees on typical balances, but it explains why a bank statement may not agree exactly with a monthly-rate calculation.
Anil's home loan rate has just been reset to 9% a year and he wants to know what rate is applied to his balance each month.
Answer: Monthly interest rate 0.75%
Forgetting to divide by 100 before using the monthly rate in a formula.
Dividing an effective annual return by 12 and treating it as exact.
Using the monthly rate on the original loan amount instead of the current balance.
Expecting bank statements to match exactly when the lender uses daily interest.
Working out one month's interest on a loan or overdraft balance.
Preparing the monthly rate before calculating an EMI or SIP by hand.
Checking the interest charged on a loan statement.
Explaining interest calculations in school and college maths.
Is this the rate used in EMI calculations?
Yes. EMI formulas change the yearly rate into a monthly rate this same way, before using it in the full EMI formula.