Loan Prepayment Calculator

See exactly how much interest you save — and how many months you shave off — when you make a part-payment or lump-sum prepayment on your loan.

🔒 Runs entirely in your browser — nothing is sent anywhere

Your loan

The principal you still owe today.

Your current annual rate.

Time left on the loan.

Your prepayment

Prepayment type

A single extra payment towards principal.

Months from now (1 = your next EMI).

Strategy

Keep your EMI the same and finish the loan sooner.

How this works

Prepaying knocks money straight off your principal — so you stop paying interest on it. Here's how we work out your saving.

1

We rebuild your loan

From your outstanding balance, rate and remaining term we compute your EMI and the normal, month-by-month interest you'd otherwise pay.

2

We apply your prepayment

A one-time lump sum or a recurring extra amount is subtracted from the principal, and the amortisation is re-run from that point.

3

We show the saving

Either you finish the loan sooner (reduce tenure) or your EMI drops (reduce EMI). The interest you avoid is your saving.

Two ways to use a prepayment

Reduce tenure (default)

Your EMI stays exactly the same, but the loan ends earlier because the outstanding principal is now smaller. This maximises interest saved and gets you debt-free faster — the better choice when your monthly budget can comfortably keep the current EMI.

Reduce EMI

The loan runs for the same number of months, but the EMI is re-calculated on the lower balance, so your monthly outgo falls. You save less interest than the tenure option, but free up cash each month. Best suited to a one-time lump-sum prepayment.

EMI is computed as P·r·(1+r)ⁿ ÷ ((1+r)ⁿ − 1), where P is the outstanding principal, r the monthly rate (annual ÷ 12 ÷ 100) and n the remaining months. Results are estimates that ignore any prepayment/foreclosure fees, insurance and taxes — confirm exact figures and charges with your lender before acting.

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Private by design. Every number stays on your device. Nothing you type is uploaded, stored or shared.

Frequently Asked Questions

Is it better to reduce the tenure or reduce the EMI when I prepay?
Reducing the tenure almost always saves more interest. When you keep the EMI the same and shorten the loan, more of every future payment goes towards principal, so the interest clock stops sooner. Reducing the EMI lowers your monthly outgo but keeps you in debt for the full remaining term, so the interest saving is smaller. Pick 'Reduce tenure' if your cash flow is comfortable; pick 'Reduce EMI' if you need breathing room in your monthly budget.
Do banks charge a penalty for prepaying a home loan?
For floating-rate home loans taken by individuals, the RBI does not allow foreclosure or prepayment charges. Fixed-rate loans, and many personal or business loans, can carry a prepayment/foreclosure fee (commonly 2–5% of the amount prepaid). Always confirm the charge with your lender and factor it against the interest you would save before deciding.
When during the loan is prepayment most effective?
As early as possible. In the first years of an EMI, the largest share of each instalment is interest, so a rupee of principal knocked off early avoids many years of future interest. The same lump sum prepaid in the last year of the loan barely moves the needle. Use the 'in which month' field to see how the timing of a one-time prepayment changes your savings.
Should I prepay the loan or invest the money instead?
Compare the after-tax return you could earn on an investment against your loan's interest rate. If your loan costs 9% and a safe investment yields less than that after tax, prepaying gives you a guaranteed, risk-free return equal to the loan rate. If you can reliably earn more elsewhere — and you value the liquidity — investing may win. Prepaying also gives peace of mind by removing debt.
Does this calculator store or send my loan details anywhere?
No. Every calculation runs entirely inside your browser using JavaScript. Nothing you type is uploaded, saved on a server, or shared — close the tab and it is gone.
How is the interest saving calculated?
The tool first builds your loan's normal month-by-month amortisation to find the baseline total interest. It then re-runs the amortisation with your prepayment applied to the outstanding principal — either ending the loan early (reduce tenure) or re-computing a lower EMI over the same term (reduce EMI). The difference between the two interest totals is your saving.

Free to use · works entirely in your browser · no account needed.