Borrowing against the roof over your head
A home equity loan is a second mortgage: the lender hands you a lump sum today, secured by the equity you have built in your home, and you repay it in fixed monthly instalments over a set term. Because the house backs the loan, the interest rate sits well below what credit cards and unsecured personal loans charge, and the payment never changes, which makes the instrument a favourite for renovations, consolidations and large planned purchases. But the security cuts both ways — the same collateral that earns you the cheap rate is the one at risk if the payments stop.
This calculator answers the two questions everyone asks before signing: what will the monthly instalment and total interest actually be, and how much am I allowed to borrow in the first place? The first half runs the classic annuity maths against the loan amount, rate and term, with an optional closing-cost switch. The second half checks the loan-to-value limit that lenders actually apply: the headroom is the property value times the acceptable LTV minus whatever is still owed on the first mortgage.
The repayment maths: a fixed monthly instalment
A home equity loan behaves like any amortizing loan: each month you pay a fixed instalment, part of which repays principal and part pays interest, and the interest is computed on the balance still outstanding. Early in the term the interest share is large because the balance is large; as the years pass the balance shrinks and the principal share of the same fixed payment grows. The monthly instalment is found with the standard annuity formula:
EMI = P × r × (1 + r)ⁿ / ((1 + r)ⁿ − 1)
where P is the amount financed, r is the monthly interest rate (the annual rate divided by 1,200), and n is the number of monthly payments — the term in years times twelve. If you borrow ₹15,00,000 at 8.5% for 15 years, the formula produces a monthly payment of roughly ₹14,770. Across 180 payments that is about ₹26.6 lakh in total, of which about ₹11.6 lakh is pure interest. The exact figures appear in the outputs and in the amortization schedule under the results.
The schedule is worth studying before you commit. Scroll to the first payment and you see interest dominating; jump to the final year and the same instalment is almost entirely principal. That shape is why prepaying an old loan saves less than people expect, and why a slightly shorter term at a modestly higher payment can cut total interest dramatically.
Closing costs: a small knob with real consequences
Home equity loans are not free to originate. Appraisal, title search, documentation and origination fees commonly total 2% to 5% of the loan, and the calculator defaults to 3% while letting you dial 0–15%. Two ways to handle the fee are modelled: roll it into the loan, which finances it at the loan's interest rate, or pay it upfront at closing, which keeps the principal untouched.
The difference compounds quietly. On a ₹15,00,000 loan with 3% closing costs, rolling in adds ₹45,000 to the principal, and at 8.5% over 15 years that ₹45,000 is repaid with roughly ₹35,000 of extra interest on top. Paying the fee upfront avoids that interest but ties up cash at a moment when you may need every rupee. The calculator displays the financed amount under both modes so the trade-off is explicit rather than assumed.
How much can you actually borrow
Lenders do not hand over your full equity; they cap the combined debt on the property at a fraction of its value. The loan-to-value ratio is the standard gatekeeper: most lenders cap total borrowing at 80% of the current value, and many stretch or shrink from there — 90% for the most creditworthy, 70% or 60% for more conservative books. The maximum home equity loan is therefore:
Max loan = home value × LTV% − outstanding mortgage balance
A home worth ₹40,00,000 with a ₹18,00,000 first mortgage and an 80% LTV cap leaves 0.80 × 40,00,000 − 18,00,000 = ₹14,00,000 of headroom. Slide the LTV selector to 90% and the same home allows ₹18,00,000; drop to 60% and only ₹6,00,000 remains. That single slider is where most dreams of renovation get reality-checked, and it updates the qualification output instantly.
One important nuance: the value used is today's realistic market value, not the purchase price and not the insured value. A registry value or a recent valuation is the honest input, because lenders will commission their own appraisal anyway and the calculator is only as good as the number you feed it.
Other gates beyond the LTV
Property value is only one of the gates. Lenders also check the borrower's credit history — weak profiles are simply declined or pushed to higher rates — and their debt-to-income ratio; a payment that pushes total debt past about 43% to 50% of income is rarely approved. The home itself must be in acceptable condition, and existing liens or title problems pause the process. The calculator models the financial gates transparently; the personal ones are for the bank.
What the outputs tell you
With the default inputs — ₹15,00,000 at 8.5% over 15 years, closing costs rolled in at 3% — the results read as a coherent story. The amount financed climbs to ₹15,45,000. The monthly instalment lands near ₹15,200, the total of all 180 payments near ₹27.4 lakh, and total interest near ₹11.9 lakh. The closing fee shows ₹45,000. The qualification panel, meanwhile, reports that at 80% LTV the same home allows about ₹14,00,000, so the requested loan fits comfortably under the cap.
Change the term to 10 years and watch the instalment jump while total interest collapses; extend to 20 years and the payment drops but the interest climbs by lakhs. This tension between cash flow and cost of borrowing is the core decision every borrower faces, and the schedule makes it concrete rather than abstract.
Reading the donut and the schedule
The donut divides the total cost into the amount financed and the interest paid, giving a single glanceable answer to the question every borrower actually asks: how much of what I repay is mine? The schedule below it tabulates every month of the term — payment number, interest portion, principal portion and remaining balance — and also rolls the totals up year by year so you can see the balance fall and the interest share shrink. Many borrowers keep a printed copy at hand to track where they stand.
When closing costs are rolled in, the donut and schedule automatically reflect the higher financed amount; toggle the inclusion off and the whole chain re-computes. Nothing about the layout requires re-entry of any other input, which keeps comparisons between lender offers — different rates, different fee structures — a matter of two quick edits rather than a full rework.
Ways to use the loan, and alternatives
The classic uses are predictable: major home improvements that repay part of their cost in property value, debt consolidation that trades 30%-plus credit card interest for a rate in the single digits, education funding, and large one-time expenses where a fixed payment plan beats a revolving line. Consolidation deserves special care: the calculator shows the maths clearly, but the maths only wins if the cards are retired and not reloaded.
Before borrowing, weigh the two main alternatives. A cash-out refinance replaces the primary mortgage entirely and works well when market rates are below your existing rate — but it resets the whole loan, not just the top-up. A home equity line of credit, or HELOC, gives flexibility to draw as needed and is better for ongoing costs like phased renovations or tuition, but its rate is usually variable and the payment uncertainty is real. The fixed-rate, fixed-payment profile of the home equity loan remains the right tool for a known sum with a known schedule.
Risk and discipline
None of the numbers on this page constitute advice, and all of them are estimates. Your bank will set the actual rate from your credit profile, the property, and its own policies, and the closing costs will appear in the final disclosure, not the brochure. Before you sign, run the worst case: a rate a full point higher, a term at the outside, and the fee paid upfront — if the payment still fits your budget comfortably, the loan is probably affordable. If it only fits at the best case, the home that secures the loan is doing too much work for comfort.
Finally, keep the schedule. Twelve years into a fifteen-year loan, when the balance has halved and the interest is down to a few thousand per month, that document is the proof that the fixed payment was worth it. The discipline of a second mortgage is the same as the first: borrow for a clear purpose, at a payment you can sustain, and repay on schedule. The calculator exists to make the second of those three visible before the ink dries.
Disclaimer
Results are provided as estimates for informational purposes only and may be inaccurate. Always verify outcomes with a qualified professional before making financial or personal decisions based on these calculations.