How to Calculate Loan EMI: Formula & Example

You do not need to do the arithmetic by hand — the Loan EMI Calculator on this site does it instantly — but understanding the formula means you can sanity-check any figure a lender gives you, and spot when a quote looks too good to be true.

The EMI formula

The standard formula is EMI = P × r × (1 + r)ⁿ ÷ ((1 + r)ⁿ − 1), where P is the loan amount (principal), r is the monthly interest rate, and n is the number of monthly payments. The monthly rate is the annual rate divided by 12 and by 100 — so a 10% annual rate becomes 0.10 ÷ 12, or about 0.00833 per month. The formula looks intimidating, but it only does one thing: it finds the fixed monthly payment that exactly clears the loan, with interest, over n months.

Two things about the formula are worth remembering. First, the EMI is fixed for the whole tenure if the rate is fixed — it does not change month to month. Second, the total interest you pay is simply (EMI × n) − P: the total of all your payments minus what you borrowed.

Worked example: a 500,000 loan at 10% for 5 years

Take a loan of 500,000 at 10% annual interest over 5 years (60 months). The monthly rate is 0.00833. Plugging the numbers into the formula gives an EMI of about 10,624 per month. Over 60 months you pay about 637,440 in total, which means the interest costs you roughly 137,440 — more than a quarter of the amount you borrowed. That is the figure to look at when comparing loans, not just the monthly payment.

Now change one variable. Shorten the tenure to 3 years (36 months) and the EMI rises to about 16,134 — but total interest falls to roughly 80,800, saving you about 56,600. Or keep 5 years and cut the rate to 8.5%, and the EMI drops to about 10,258 with total interest around 115,500. Small changes in rate and tenure move the total cost by far more than most people expect, which is why it pays to try a few combinations before signing anything.

Step by step

1. Enter the loan amount — the principal you actually borrow, after any down payment.
2. Enter the annual interest rate exactly as the lender quotes it.
3. Enter the tenure in years or months, whichever the calculator asks for.
4. Read the EMI, the total interest and the total amount payable — all three matter.
5. Try a shorter tenure and a lower rate to see how much each one saves you.

Common mistakes

• Using the annual rate as the monthly rate. The formula needs the monthly rate: annual rate ÷ 12. Using 10% as a monthly rate gives a wildly wrong EMI.
• Comparing only the EMI. A longer tenure gives a smaller EMI but much more total interest. Always compare total interest too.
• Forgetting fees. Processing fees, insurance and prepayment charges are not in the EMI. Ask the lender for the total cost, not just the monthly figure.
• Borrowing to the maximum you qualify for. Lenders approve more than is comfortable. A common rule is to keep all EMIs below about 40% of your take-home pay.
• Ignoring floating rates. If the rate is floating, the EMI — or the tenure — can change. Check which one the lender adjusts when rates move.

Tips before you borrow

Paying even a little extra each month cuts the total interest more than it looks: an extra 1,000 a month on the example above shortens the loan by several months. A larger down payment has the same effect, because interest is charged on a smaller principal. And if you already have a loan, check whether a balance transfer to a lower rate is worth it — but count the transfer fee and the remaining tenure before you decide, because a lower rate over a longer tenure can still cost more overall.

Frequently asked questions

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