Car loan EMI calculator:
how down payment and tenure change the cost

How a car loan EMI is worked out

The amount you finance is not the sticker price. It is the on-road price, meaning the car plus registration, insurance and other charges you pay, less your down payment and any trade-in value, plus any fees you choose to add to the loan.

From there the EMI depends on three things: the amount financed, the interest rate and the number of months. The down payment changes the first, the lender's offer sets the second and your tenure choice sets the third.

Lenders usually finance only a share of the price, so check what down payment is asked before you shortlist a car.

As a hypothetical, suppose the ex-showroom price is ₹8,50,000 and registration, insurance and other charges add ₹1,25,000. The on-road price is ₹9,75,000, and that is the number to use, not the advertised one.

Car loan EMI formula

1. 1Add up the on-road price and any fees you will finance.
2. 2Subtract the down payment and trade-in value to get P.
3. 3Divide the annual rate by 12 and write it as a decimal for r.
4. 4Multiply the years by 12 for n, then apply the formula.

This is a reducing-balance loan, where each month's interest is charged on what you still owe. Banks generally quote this way, but some dealers quote a flat rate, which is much more expensive for the same headline number.

Example: ₹10 lakh car, ₹2 lakh down payment, 5 years at an assumed 9%

The growth factor is 1.0075⁶⁰ ≈ 1.5657. So ₹8,00,000 × 0.0075 × 1.5657 ÷ 0.5657 ≈ ₹16,607.

In the first month, interest is ₹8,00,000 × 0.0075 = ₹6,000, so about ₹10,607 of the EMI repays principal. The split gradually shifts towards principal as the balance falls.

The interest is about 24.6% of the amount financed. And because interest is front-loaded, after 24 EMIs, which total about ₹3,98,560, roughly ₹5,22,227 of the loan, or 65%, is still outstanding. That is the figure to ask about before closing a car loan early.

How the down payment changes the EMI

Every extra ₹1,00,000 you put down lowers the EMI by about ₹2,076 and the total interest by about ₹24,550. Moving from nothing down to ₹3,00,000 cuts the EMI by about ₹6,228 a month.

You can also run the formula backwards. If ₹15,000 is the most you want to pay each month, a 5-year loan at an assumed 9% supports about ₹7,22,600. Add your down payment to that to get the on-road price you can consider.

A bigger down payment means less debt, but it also uses savings. Keep enough cash for registration, insurance, running costs and an emergency fund before you commit the rest.

Tenure and rate: what they do to the cost

A longer tenure shrinks the EMI but raises the interest sharply. Stretching from five to seven years drops the EMI by about ₹3,735 and adds about ₹84,800 in interest.

Choose the tenure by working from your EMI ceiling: take the shortest tenure whose EMI you can pay without touching savings. A longer tenure is a way to protect cash flow, not a way to make the car cheaper.

Each percentage point on the rate changes the EMI by roughly ₹390 here, which adds up to about ₹23,500 over the loan. It is worth asking more than one lender.

Flat rate versus reducing rate

A flat rate charges interest on the original amount for the whole tenure. At a flat 6% on ₹8,00,000 for five years, interest is ₹8,00,000 × 0.06 × 5 = ₹2,40,000. Add it to the principal and divide by 60 months, and the EMI is ₹17,333.

A reducing-balance loan with that EMI would be about 10.8% a year. The flat 6% looks far cheaper than a 9% reducing rate, but it is in fact nearly two percentage points more expensive.

The gap widens as the flat rate rises. For a five-year loan, a flat 7% is equivalent to about 12.5% on a reducing balance, and a flat 8% to about 14.1%.

What the EMI leaves out, and how to compare offers

The EMI is the cost of the loan, not the cost of the car. Fuel, insurance renewals, servicing, tyres, parking and depreciation come on top. Some costs also sit inside the loan paperwork.

• Processing fees and other charges. A 1% fee added to the loan raises the financed amount to ₹8,08,000 and the EMI to about ₹16,773.
• Pre-payment or foreclosure charges, if you plan to close the loan early.
• Insurance, which is a yearly cost and may be required as a condition of the loan.
• A rate change, if the loan is on a floating rate.

Comparing two offers needs more than the rate. Put the same four numbers side by side before you choose.

• The EMI and the total repaid over the whole tenure.
• Processing and documentation fees, and whether they are added to the loan.
• The foreclosure or part-payment terms.
• Whether the rate is fixed or floating, and on what benchmark.

A used car often carries a higher rate and a shorter maximum tenure than a new one, so run the formula with the lender's own figures instead of reusing a new-car number.

A simple check is the EMI as a share of take-home pay. At ₹16,607, an ₹80,000 take-home gives about 21%, before fuel and running costs. Decide your own ceiling before you visit the showroom.