How to Calculate Loan EMI: The Formula Behind Your Monthly Payment
Understand what an EMI is, the exact formula used to calculate it, how principal and interest split over time, and why loan tenure dramatically changes what you pay.
Whether you are financing a home, a car, or an education, your loan is almost always repaid through an EMI, an Equated Monthly Installment. Understanding how that single number is calculated helps you compare offers, plan your budget, and see exactly how much a loan really costs.
What Is an EMI?
An EMI is a fixed payment you make to a lender every month until the loan is fully repaid. Each installment covers two things: a portion of the original amount you borrowed (the principal) and the interest charged on the outstanding balance. Although the monthly amount stays constant, the split between principal and interest shifts over time.
The EMI Formula
EMI is calculated using the principal, the monthly interest rate, and the number of monthly installments:
EMI = P x r x (1 + r)^n / ((1 + r)^n - 1)
P = principal loan amount
r = monthly interest rate (annual rate / 12 / 100)
n = number of monthly installments
Example: P = 500000, annual rate = 9%, tenure = 5 years
r = 0.09 / 12 = 0.0075, n = 60
EMI = about 10,379 per monthHow Principal and Interest Split Over Time
This surprises many borrowers. In the early months, most of your EMI goes toward interest because the outstanding balance is high. As the balance shrinks, more of each payment chips away at the principal. This schedule is called an amortization table.
- Early payments: mostly interest, little principal.
- Middle payments: the split gradually balances out.
- Final payments: mostly principal, very little interest.
- This is why paying extra early in a loan saves the most on total interest.
Why Loan Tenure Matters
A longer tenure lowers your monthly EMI, which feels easier on the budget, but it increases the total interest you pay over the life of the loan. A shorter tenure means higher monthly payments but far less interest overall. Always look at the total cost, not just the monthly figure.
Two loans with the same interest rate can cost wildly different amounts depending on tenure. Compare the total repayment, not only the monthly EMI.
To model different amounts, rates, and tenures instantly, use the Loan EMI Calculator. It runs entirely in your browser, so your financial figures never leave your device.