Loan Prepayment Calculator

Loan prepayment means paying more than your scheduled EMI, either as a one-time lump sum or as a regular extra amount, to reduce the principal faster than the original schedule. It matters because of how reducing-balance loans work: the bank charges interest each month on whatever principal is still outstanding, so the faster you bring that principal down, the less interest accrues over the life of the loan. In the early years of a long loan the outstanding balance is high and most of each EMI goes towards interest rather than principal, which is exactly why a prepayment made early has such an outsized effect — it removes principal that would otherwise have been generating interest for many years.

A prepayment calculator matters because the savings are large and genuinely hard to estimate by intuition. On a ₹50 lakh home loan at 8.5% over twenty years, a single ₹5 lakh prepayment in the first year can save roughly ₹16 lakh in interest — more than three times the amount prepaid — and bring the loan to a close about four years sooner. Without a calculator, most borrowers have no way to see that a prepayment of a few lakh translates into a many-lakh reduction in total interest, so they cannot weigh prepaying against other uses of the same money, such as investing it.

The tool also makes explicit the choice every borrower faces after a prepayment: reduce the tenure or reduce the EMI. Keeping the EMI unchanged and letting the loan finish early captures the maximum interest saving, because the higher payment continues to attack the principal. Reducing the EMI instead — recomputing a smaller monthly payment over the original tenure — frees up monthly cash flow but saves less interest overall. Seeing both outcomes side by side lets you decide whether you value being debt-free sooner or having more room in your monthly budget.

Enter the loan details. Type the loan amount, the annual interest rate, and the original tenure in years. These define the baseline EMI and the total interest you would pay with no prepayment, which the tool uses as the comparison point.

Add your prepayment. Enter a one-time lump sum and the month you plan to make it, a recurring monthly extra you will pay alongside the EMI, or both. The earlier a one-time prepayment is made, the more it saves, because it removes principal that would otherwise accrue interest for longer.

Choose what to reduce. Select reduce-tenure to keep your EMI the same and finish the loan early, or reduce-EMI to keep the original tenure and lower your monthly payment. Reduce-tenure directs the full benefit of the prepayment at closing the loan faster and saves the most interest; reduce-EMI spreads the benefit across a smaller monthly payment and eases cash flow instead. The result updates immediately when you switch between the two, so you can see the exact difference for your own loan rather than relying on a rule of thumb.

Read the savings. The panel shows your original EMI, the interest you save against the no-prepayment baseline, and either how many months earlier the loan closes (in reduce-tenure mode) or how much lower your new EMI becomes (in reduce-EMI mode). Adjust the prepayment amount, the month you make it, or the mode to compare scenarios side by side before committing any money, and note that a prepayment made earlier in the loan consistently saves more than the same amount paid later. Use the figures to decide whether prepaying beats leaving the money invested elsewhere.