Understanding EMI: How Loan Instalments Are Calculated
An EMI, or Equated Monthly Instalment, is the fixed amount you pay each month to repay a loan. It combines interest and a part of the principal. Understanding how it is built helps you compare lenders and decide how much to borrow.
The formula
EMI = P × r × (1 + r)n / ((1 + r)n − 1), where P is the loan amount, r is the monthly interest rate (annual rate ÷ 12 ÷ 100) and n is the number of monthly payments. For example, a loan of 10,00,000 at 9 percent a year for 10 years has r = 0.0075 and n = 120, giving an EMI of about 12,668. You do not need to do this by hand: the EMI Calculator shows the EMI, total interest and total payment instantly.
Interest comes first
In the early years most of each instalment is interest, because interest is charged on the full outstanding balance. As the balance falls, a larger share goes to principal. This is why prepaying early saves much more interest than prepaying near the end of the loan.
Tenure versus EMI
A longer tenure lowers the EMI but increases the total interest. On the example above, stretching 10 years to 20 years reduces the EMI to about 8,997 but raises total interest from roughly 5.2 lakh to about 11.6 lakh. A good approach is to choose the shortest tenure whose EMI fits comfortably in your budget.
How much EMI can you afford?
A common guideline is that all your EMIs together should not exceed 40 to 50 percent of your monthly take-home income, and many advisers prefer lower. Keep an emergency fund as well, so that a job gap does not force you to miss payments.
What the calculator does not include
- Processing fees, insurance and other charges.
- Rate changes on floating-rate loans.
- Different methods lenders use to compute interest, such as daily reducing balance.
For a home loan, also try the Mortgage Calculator, which starts from the property price and the down payment. For savings and investments, the Interest Calculator compares simple and compound interest.
This guide is educational and is not financial advice. Check the terms in your loan agreement before you borrow.