Whether you're taking a home loan, car loan, or personal loan, your bank will quote you an EMI — Equated Monthly Installment — before you sign anything. Understanding how that number is actually calculated helps you compare loan offers properly, instead of just trusting whatever number a lender shows you.
The EMI Formula Banks Actually Use
EMI = P × r × (1+r)^n / ((1+r)^n − 1)
Where:
- P = Principal (the loan amount you're borrowing)
- r = Monthly interest rate (your annual rate ÷ 12 ÷ 100)
- n = Loan tenure in months (years × 12)
It looks intimidating, but it's really just spreading your loan and its interest evenly across every month of the tenure, so each payment is identical.
Worked Example
Say you borrow ₹5,00,000 at 10% annual interest for 5 years.
- P = 500000
- r = 10 ÷ 12 ÷ 100 = 0.00833
- n = 5 × 12 = 60 months
Plugging these into the formula gives an EMI of approximately ₹10,624 per month. Over 60 months, you'll pay back roughly ₹6,37,440 total — meaning about ₹1,37,440 of that is pure interest.
Try the EMI Calculator to run your own numbers instantly
Why a Longer Tenure Isn't Always "Cheaper"
A longer tenure lowers your monthly EMI, which feels more affordable — but it also means you pay interest for a longer period, so the total interest paid goes up significantly. A shorter tenure raises your monthly EMI but reduces the total interest paid over the life of the loan. There's no universally "right" answer here — it depends on what monthly payment you can comfortably afford versus how much total interest you're willing to pay.
What Changes Your EMI Most
- Interest rate has a compounding effect — even a 1% difference in rate can change your total interest by a meaningful amount over a long tenure
- Tenure length trades off monthly affordability against total cost, as covered above
- Principal amount scales your EMI roughly linearly — borrowing double means paying roughly double each month, all else being equal
A Quick Word of Caution
This formula gives you the base EMI on the principal and interest only. Real loan offers often include processing fees, insurance add-ons, or prepayment penalties that aren't part of this calculation. Always check the full cost breakdown a lender provides, not just the EMI figure alone, before comparing two loan offers.
Calculate your own EMI in seconds — just enter loan amount, interest rate, and tenure