About this tool
What is an EMI?
An Equated Monthly Instalment is the fixed amount you pay a lender each month until a loan is fully repaid. Every instalment contains two parts: interest on the outstanding balance, and repayment of principal. The total stays constant, but the mix changes over time.
In the early months most of your payment is interest because the outstanding balance is large. As the balance falls, the interest component shrinks and more of each instalment goes towards principal. This is called amortisation, and it explains why paying off a loan two years in barely dents the principal on a twenty-year mortgage.
The EMI formula
EMI = P × r × (1 + r)ⁿ ÷ ((1 + r)ⁿ − 1), where P is the principal, r is the monthly interest rate (annual rate ÷ 12 ÷ 100) and n is the tenure in months.
A worked example: ₹10,00,000 borrowed at 9% for 10 years gives r = 0.0075 and n = 120, producing an EMI of about ₹12,668. Over the full term you repay roughly ₹15.2 lakh — about ₹5.2 lakh of it interest. Seeing that total interest figure, rather than just the monthly number, is the single most useful thing a calculator does.
What actually moves your EMI
Three inputs determine everything, and they do not behave the same way.
- Principal — scales the EMI linearly. Borrow 10% less and pay 10% less each month.
- Interest rate — even a 0.5% difference costs lakhs over a long tenure, which is why refinancing is worth checking.
- Tenure — a longer term lowers the monthly payment but sharply increases total interest. Stretching a home loan from 15 to 25 years can nearly double the interest you pay.
- Prepayments — any lump sum applied to principal removes all the future interest that principal would have generated, so early prepayments are dramatically more valuable than late ones.
Fixed vs floating rates, and the costs beyond EMI
A fixed rate locks your instalment for the term, giving certainty at the price of a slightly higher rate. A floating rate moves with a benchmark such as the repo rate; lenders usually keep the EMI steady and adjust the tenure instead, which means a rate rise can quietly add years to your loan. Check which behaviour your lender applies.
The EMI is not the whole cost of borrowing. Processing fees (typically 0.5–1% of the loan), documentation and legal charges, mandatory insurance, stamp duty on the mortgage deed, and prepayment penalties on fixed-rate loans all sit outside the monthly figure. When comparing offers, compare the annual percentage rate including fees rather than the headline rate.
How much should you borrow?
A widely used guideline is that total EMIs across all loans should stay under 40% of your take-home pay, and a home loan alone under about 30%. Lenders apply their own fixed-obligation-to-income ratio and will generally approve less if you have existing debt.
Use the calculator to work backwards: decide the EMI you can comfortably sustain alongside savings and an emergency fund, then see what principal and tenure that supports. Borrowing to your approved maximum leaves no room for a rate rise, a medical bill or a gap between jobs.
Tips for best results
- 01Shorten the tenure rather than the principal when you can afford it — it is the fastest way to cut total interest.
- 02Make one extra EMI a year; on a twenty-year loan that alone can shave several years off the term.
- 03Compare offers on total cost including processing fees, not the advertised interest rate.
- 04On floating-rate loans, ask whether a rate rise increases your EMI or extends your tenure.
- 05Check for prepayment charges before signing; floating-rate retail loans in India generally cannot levy them for individual borrowers.
- 06Keep total EMIs under 40% of take-home pay, and keep three to six months of expenses in reserve.
- 07Re-run the numbers before agreeing to a top-up loan — it often resets your amortisation clock to the expensive early years.
Frequently asked questions
How is EMI calculated?+
EMI = P × r × (1+r)ⁿ / ((1+r)ⁿ − 1), where P is principal, r is the monthly rate and n is the number of months.
Does a longer tenure save money?+
It lowers the monthly payment but increases total interest, often substantially. Choose the shortest tenure you can comfortably service.
How do prepayments help?+
A lump sum applied to principal eliminates all future interest on that amount. The earlier in the loan you prepay, the larger the saving.
Is the result exact?+
It matches the standard amortisation formula. Your lender's figure may differ slightly because of rounding, the disbursal date, or fees added to the principal.
Can I use it for home, car and personal loans?+
Yes. The formula is identical; only the typical rate and tenure differ.
Are my figures stored?+
No. The calculation runs in your browser and nothing you enter is transmitted or saved.
Does it include processing fees or insurance?+
No. Those are one-time or separate costs — add them when comparing the true cost of two offers.