Loan Interest Calculator
Most loan calculators focus on your monthly instalment. This one focuses on a different question: how much will this loan really cost you in interest, and how is that cost spread out over the years you'll be repaying it? Enter the loan amount, interest rate and tenure to see your total interest payable, what that interest works out to as a percentage of the amount you borrowed, and a year-wise breakdown showing exactly how the interest portion of your payments is front-loaded and falls every year.
Fill in the form and select "Calculate" to see your results here.
What is the Loan Interest Calculator?
This calculator is built around a single question: how much interest will you actually pay on a loan, and how is that cost distributed over the life of the loan? That's a different question from "what's my monthly payment," which is what the EMI Calculator answers — that calculator's total interest figure is just one summary tile alongside the EMI. Here, total interest and interest-as-a-percentage-of-principal are the headline results, and the year-wise table exists specifically to show how the interest you pay is heavily front-loaded in the early years and keeps shrinking every year after that, even though your EMI never changes. If you instead need the full month-by-month or year-by-year figures for both principal repaid and the remaining loan balance, use the Loan Amortization Calculator, which is built for that complete schedule rather than the interest-cost lens this page focuses on.
How to use this calculator
- Enter the loan amount you plan to borrow, or the outstanding amount on an existing loan.
- Enter the annual interest rate quoted by the lender.
- Enter the loan tenure in years or months, whichever your lender's offer is stated in.
- Select "Calculate Interest" to see your total interest payable, interest as a percentage of principal, and a year-wise breakdown of how much of each year's payments went to interest versus principal.
Formula
Total interest is simply the difference between everything you eventually pay back and what you originally borrowed. The more useful number for comparing loans is interest as a percentage of principal, since it expresses the interest cost relative to the loan size rather than as a raw rupee figure. The year-wise interest share, calculated from the same reducing-balance amortization schedule used by the EMI and Amortization calculators, shows how that cost is distributed unevenly across the tenure rather than paid evenly every year.
Example
Consider a loan of ₹25,00,000 at 8.5% per annum, repaid over a tenure of 240 months (20 years). The EMI Calculator's formula gives a monthly instalment of ₹21,695.58. Over the full 240 months you repay a total of ₹52,06,939.40, of which ₹27,06,939.40 is interest — that's about 108.3% of the amount you originally borrowed, meaning you end up paying more in interest than you borrowed in the first place.
The year-wise breakdown shows exactly where that interest is concentrated. In year 1, you pay ₹2,10,591.24 in interest against just ₹49,755.73 in principal — interest makes up about 80.9% of every rupee you pay that year. By year 20, the final year, that flips almost entirely: you pay ₹11,600.87 in interest against ₹2,48,746.10 in principal, so interest is down to just 4.5% of that year's payments. The EMI is identical in both years; only the split between interest and principal has changed, because interest is charged on a shrinking outstanding balance.
Factors that affect your total interest cost
- Loan amount. A larger principal increases total interest roughly in proportion, all else being equal.
- Interest rate. Because interest compounds on the outstanding balance every month, even a small difference in rate has an outsized effect on total interest over a long tenure.
- Tenure. A longer tenure lowers the monthly EMI but increases total interest, since the balance takes longer to pay down and accrues interest for more months. A shorter tenure does the opposite.
- Prepayments. Any extra payment made toward principal, whether a recurring top-up or a one-time lump sum, immediately reduces the balance that future interest is calculated on — which is why even modest prepayments can meaningfully cut total interest on a long-tenure loan.
Frequently Asked Questions
Indian lenders charge interest on the reducing-balance method: interest for a given month is calculated only on the loan balance still outstanding at the start of that month. Early on, almost the entire loan is still outstanding, so a large share of each EMI is consumed by interest and only a small share reduces the principal. As the balance shrinks year after year, the interest portion of each EMI shrinks with it and the principal portion grows, even though the EMI itself stays fixed.
Yes. For the same loan amount and interest rate, stretching the tenure lowers your monthly EMI but increases the number of months over which interest keeps accruing on the outstanding balance, so total interest paid rises. A shorter tenure raises the EMI but reduces total interest. This calculator lets you compare tenures on the same loan amount and rate to see that trade-off in exact rupee terms rather than just a feeling of "lower EMI is better."
Two loan offers with similar EMIs can have very different total interest costs once tenure and rate combine differently. Interest as a percentage of principal tells you, in one number, how much extra you are paying over and above the amount you borrowed — a loan where interest works out to 60% of principal is meaningfully cheaper than one where it works out to 110%, even if the monthly EMIs look similar. It is a more complete comparison than EMI alone, which only tells you what fits your monthly budget.
The EMI Calculator answers "what will my monthly payment be?" and shows total interest as one summary figure alongside it. This calculator is built specifically around the interest cost itself: it highlights interest as a percentage of principal and, more importantly, shows a year-wise breakdown of how the interest portion of your payments is front-loaded and falls every year — the kind of detail the EMI Calculator's summary view doesn't surface. If you need the full month-by-month or year-by-year figures for both principal and remaining balance, use the Loan Amortization Calculator instead.
The three levers are the loan amount, the interest rate, and the tenure. Borrowing less, negotiating a lower rate, or choosing a shorter tenure all reduce total interest directly. If the loan is already running, making prepayments toward the principal — even occasional lump sums — cuts the balance interest is calculated on for the rest of the tenure, which is the same effect a shorter tenure has. Use the Home Loan Prepayment Calculator to see how much interest a specific prepayment would save on an existing loan.
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Calculations are estimates based on the information entered, using a fixed interest rate and the standard reducing-balance amortization method. They do not account for processing fees, insurance, prepayment charges, or changes to a floating interest rate, and are not a substitute for the amortization schedule provided by your lender. See our full disclaimer.