How an EMI is calculated
An EMI (Equated Monthly Instalment) is the fixed amount you pay a lender every month until a loan is cleared. Each instalment is the same size, but its composition shifts: early payments are mostly interest, later ones are mostly principal. That split is why paying a loan off early saves so much — you skip the interest-heavy years.
Three inputs determine the EMI: the amount borrowed, the annual interest rate, and the tenure. Everything else — total interest, the amortisation schedule, the effect of a prepayment — follows from those three.
Worked example
A 10,00,000 home loan at 9% annual interest over 10 years. The monthly rate is 0.09 / 12 = 0.0075, and the tenure is 120 months.
| Input | Value |
|---|
| Principal (P) | 10,00,000 |
| Annual rate | 9% |
| Tenure | 10 years (120 months) |
| Monthly EMI | 12,668 |
| Total paid | 15,20,109 |
| Total interest | 5,20,109 |
Over ten years the interest comes to roughly 52% of the amount borrowed. Stretch the same loan to 20 years and the EMI drops to about 8,997 — but total interest more than doubles, to around 11,59,000. A longer tenure buys monthly breathing room at a steep lifetime cost.
How to use this calculator
- Enter the loan amount you actually need — not the maximum sanctioned.
- Enter the annual interest rate quoted by the lender.
- Set the tenure in years, then compare a shorter tenure alongside it.
- Read the total interest figure, not just the EMI — that is the real price of the loan.
- Try a part-prepayment in year two or three to see how much interest it removes.
Frequently asked questions
Does a lower EMI mean a cheaper loan?
No — usually the opposite. A lower EMI almost always comes from a longer tenure, and a longer tenure means more months of interest. Compare loans on total interest paid, not on the monthly instalment.
What is the difference between a fixed and a floating rate?
A fixed rate keeps your EMI constant for the whole tenure. A floating rate moves with a benchmark, so your EMI or tenure changes when the benchmark moves. Fixed rates are typically quoted a little higher as the price of that certainty.
How does prepayment reduce interest?
A prepayment is applied directly to the outstanding principal. Since interest each month is charged on that balance, removing principal early removes every future interest charge it would have generated. Prepaying in the first third of the tenure has by far the largest effect.
Should I reduce the EMI or the tenure when I prepay?
Reducing the tenure saves more. Keeping the EMI the same and shortening the loan cuts total interest significantly; lowering the EMI while keeping the tenure gives you monthly relief but far smaller lifetime savings.
Why does my bank's EMI differ slightly from this figure?
Lenders may add processing fees, insurance or GST to the amount financed, and some compute interest on a daily reducing balance rather than monthly. Those adjustments shift the EMI by a small margin. Treat this figure as a close estimate for comparison, and the sanction letter as final.
What EMI can I comfortably afford?
A common guideline is to keep all EMIs combined under 40% of net monthly income, with home loans alone under 30%. Lenders may approve more; affordability and eligibility are not the same thing.
This calculator is an educational tool. Results are estimates based on the inputs you provide and do not constitute financial advice. Verify figures with your bank, broker or a qualified advisor before acting on them.