HELOC Calculator

A Home Equity Line of Credit (HELOC) is a revolving credit line secured by your home, similar to a credit card except backed by the value of your house instead of just your promise to pay. You can draw, repay, and re-draw during a fixed "draw period" (typically 10 years), paying interest-only on the outstanding balance. After draw ends, the credit line closes and you enter a "repayment period" (typically 20 years) where the outstanding balance amortises with principal-plus-interest payments. Unlike a cash-out refinance, a HELOC is a second mortgage — your first mortgage stays untouched. This makes HELOCs especially attractive when your existing mortgage is at a much lower rate than current refinance rates would be (the situation for millions of US homeowners who locked in 2-4% mortgages in 2020-2021).

The LTV math that determines your borrowing limit

Lenders cap the combined Loan-to-Value (CLTV) — your first mortgage plus the HELOC — as a percentage of home value. Most banks cap at 80-85%, credit unions sometimes 90%, specialty lenders 95%, and VA/military 100% in rare cases. A home worth $600K with a $350K first mortgage and an 85% CLTV cap means total allowable debt is $510K, leaving $160K of available HELOC. The lower the cap, the safer the loan for the lender — and the smaller your line. Lower CLTV caps also typically come with lower interest rates because the lender has more equity cushion. A 75% LTV HELOC often prices 0.5-1.0% below an 85% LTV HELOC at the same lender. If you don't need the maximum, taking less line at a lower LTV usually saves money long-term.

The other gotcha: lenders re-evaluate home value during the draw period. In a sharp housing downturn — as happened to many homeowners in 2008-2010 — lenders can "freeze" or even reduce your unused credit line if they think your equity cushion has eroded. Hundreds of thousands of US homeowners had HELOCs frozen during the 2008 financial crisis, including credit lines they'd never tapped. The credit line is a promise, not a guarantee — and a downturn can break the promise at the worst possible time.

The ASEAN angle — equity loans look different in APAC

HELOCs in the strict US sense aren't widely offered across Singapore, Malaysia, Indonesia, the Philippines, Thailand, or Vietnam. Most APAC banks instead offer "term loans secured by property" or "home equity loans" — closed-end second mortgages with fixed terms and lump-sum disbursement, not the revolving credit line model. Singapore's DBS, OCBC, and UOB all offer "Home Equity Loans" or "Property Term Loans" but not draw-and-repay revolving HELOCs. For retirees, the closest equivalent is the HDB Lease Buyback Scheme or private-bank reverse mortgages, which let elderly owners monetise home equity for retirement income. Malaysia's banks offer term loans secured by property at LTVs up to 90%, but again — fixed disbursement, not a revolving line. Indonesia's KPR (Kredit Pemilikan Rumah) ecosystem is mortgage-first; equity extraction is unusual. The takeaway for APAC homeowners: if you want HELOC-style borrowing flexibility, you typically need to apply for an overdraft secured by your property, which exists at most major regional banks but with paperwork and fees comparable to a refinance.

A HELOC is a credit card backed by your house. Used for high-ROI purposes — home improvement, education, debt consolidation — it's one of the cheapest sources of long-term capital. Used carelessly, it's the fastest path to losing your home.

When HELOC beats cash-out refinance — and when it doesn't

HELOC wins when your existing mortgage rate is significantly lower than current refinance rates. If you locked a 3% mortgage in 2021 and current rates are 7%, refinancing the full mortgage to extract equity means re-financing the whole balance at 7% — far more expensive than carrying the original mortgage and adding a smaller HELOC at 8%. The math: $400K at 3% costs $1,686/month; refinancing $500K (including $100K cash-out) at 7% costs $3,327/month — vs keeping the original mortgage ($1,686) + a $100K HELOC at 8.5% ($868/month amortising) for a combined $2,554. The HELOC route saves $773/month even at a higher HELOC rate. Cash-out refi wins when (a) you need a lot of cash (HELOCs cap out around $250-500K depending on lender), (b) you want a fixed rate (HELOCs are variable), or (c) your existing mortgage rate is close to current rates anyway.

Common HELOC use cases — ranked by financial sense

Home improvement — usually the best use. Adds value back to the property securing the loan, and the interest may be tax-deductible in the US under the post-2018 rules (the loan must be used to "buy, build, or substantially improve" the home). Debt consolidation — strong case when consolidating 20-25% credit card debt into 8-9% HELOC, but only if the borrower changes the spending behaviour that created the debt; otherwise the cards refill and the home is now collateral for the original problem. Education funding — defensible but federal student loans are often cheaper and have better deferral options. Business capital — high-risk; putting personal residence at stake for business venture is rarely the optimal capital stack. Investment portfolio leverage — controversial; some sophisticated investors do this, but margin calls during downturns mean potential forced selling at the worst time. Vacation, wedding, luxury consumption — almost never makes sense; you're borrowing against your home to pay for a depreciating experience.

The variable-rate risk most borrowers underestimate

HELOC rates are tied to the US prime rate (currently around 7.5-8%) plus a lender margin (typically 1-2%). When the Federal Reserve raises rates, your HELOC rate rises within 30-60 days — there's no rate-lock for variable HELOCs. Borrowers who took out HELOCs at 4-5% in 2021 watched them climb to 8-9% by 2024 — nearly doubling their interest cost. If you draw heavily and rates move against you, your interest-only payment can rise from $400/month to $800/month in 18 months. Build a buffer: stress-test your budget at HELOC rate +3% before drawing. Some lenders offer "fixed-rate conversion" features that let you lock a portion of the balance at a fixed rate — useful if you want predictability on a large draw.