Free HELOC Calculator (2026)
Calculate HELOC draw and repayment costs. Calculate instantly — no signup required. Updated for 2026.
What Is a HELOC Calculator?
A HELOC (Home Equity Line of Credit) calculator estimates the costs associated with a revolving credit line secured by your home equity. Unlike a traditional home equity loan that provides a lump sum, a HELOC works like a credit card — you draw funds as needed during a “draw period” (typically 5-10 years) and only pay interest on the amount currently borrowed. After the draw period ends, you enter the “repayment period” (typically 10-20 years) where you repay both principal and interest.
HELOCs are commonly used for home renovations, debt consolidation, education expenses, and emergency funds. Because they are secured by your home, interest rates are significantly lower than credit cards or personal loans — but there is a critical risk: if you cannot make payments, you could lose your home.
How a HELOC Is Calculated
Maximum Credit Line:
Available Equity = (Home Value × Max LTV) − Current Mortgage Balance
Most lenders allow a combined LTV (CLTV) of up to 85%.
Interest-Only Payment (Draw Period):
Monthly Payment = Outstanding Balance × (Annual Rate ÷ 12)
Fully Amortizing Payment (Repayment Period):
Standard amortization formula on the outstanding balance over the remaining term.
Step-by-Step Example
- Home Value: $525,000
- Current Mortgage Balance: $310,000
- Max CLTV: 85%
- Max HELOC Line: ($525,000 × 0.85) − $310,000 = $446,250 − $310,000 = $136,250
If you draw $75,000 at a variable rate of 8.25%:
Draw Period Payment: $75,000 × (0.0825 ÷ 12) = $515.63/month (interest only)
Repayment Period Payment (15 years): Approximately $727/month (principal + interest)
Total interest over the full HELOC lifecycle: approximately $56,800
When Should You Use This Calculator?
- Planning a home renovation: Determine how much equity you can access and what the monthly carrying cost would be during and after the project.
- Consolidating high-interest debt: Compare HELOC interest costs against credit card rates — a HELOC at 8% is dramatically cheaper than credit cards at 20-25%.
- Evaluating HELOC vs. home equity loan: A HELOC offers flexibility (draw only what you need), while a home equity loan offers rate certainty (fixed rate on the full amount).
- Emergency fund planning: Some homeowners open a HELOC as a backup emergency fund — you only pay interest when you actually draw on it.
Tips for Getting Accurate Results
- HELOC rates are typically variable: Most HELOCs are tied to the prime rate. As the Fed changes rates, your HELOC payment will adjust accordingly. Model scenarios with rates 1-2% higher than current levels.
- Plan for the payment shock: When the draw period ends and the repayment period begins, your payment can increase significantly because you are now paying principal too.
- Interest may be tax-deductible: HELOC interest is tax-deductible only when the funds are used to “buy, build, or substantially improve” the home securing the HELOC (per the 2017 Tax Cuts and Jobs Act).
- Avoid using a HELOC for consumption: Because your home is collateral, using a HELOC for vacations, cars, or lifestyle spending puts your home at risk for depreciating assets.
- Watch for annual fees and early termination fees: Some HELOCs charge $50-$100 annual maintenance fees and $300-$500 if you close the line within 3 years.
Key Takeaways
- HELOCs provide flexible access to home equity at rates significantly lower than credit cards or personal loans.
- Your maximum line of credit is based on a combined LTV of typically 85% minus your existing mortgage balance.
- Interest-only payments during the draw period keep costs low, but the transition to full repayment can increase payments by 30-50%.
- Your home is collateral — defaulting on a HELOC can lead to foreclosure, so borrow responsibly.
Frequently Asked Questions
How much equity can I borrow with a HELOC?
Most lenders allow you to borrow up to 85% of your home’s appraised value, minus your existing mortgage balance. For a home worth $525,000 with a $310,000 mortgage, you could access up to $136,250 ($525K × 85% − $310K). Some lenders offer up to 90% CLTV for borrowers with excellent credit. The exact amount depends on your credit score, income, existing debts, and the lender’s specific guidelines.
What is the difference between a HELOC and a home equity loan?
A HELOC is a revolving credit line (like a credit card) with variable rates where you draw funds as needed and pay interest only on what you use. A home equity loan is a lump-sum loan with a fixed rate and fixed monthly payments. Choose a HELOC for ongoing or uncertain expenses (like phased renovations). Choose a home equity loan for one-time expenses with a known cost (like a specific project) where you want payment predictability.
Are HELOC interest rates fixed or variable?
Most HELOCs have variable interest rates tied to the prime rate (currently around 8.50% in 2026). Your HELOC rate is typically prime plus a margin (0-2%), so rates could be 8.50-10.50%. When the Federal Reserve changes its benchmark rate, your HELOC rate and payment adjust accordingly. Some lenders offer fixed-rate conversion options that let you lock in a portion of your balance at a fixed rate during the draw period.
Can I lose my home if I default on a HELOC?
Yes. A HELOC is secured by your home, which means the lender has the legal right to foreclose if you fail to make payments. This makes HELOCs lower risk for the lender (hence lower rates) but higher risk for you compared to unsecured debt. If you are considering a HELOC, ensure you can comfortably afford the payments even during the repayment period and in a higher interest rate environment. Never borrow more than you can reliably repay.
Is HELOC interest tax deductible?
Under current tax law (since the 2017 Tax Cuts and Jobs Act), HELOC interest is tax-deductible only if the funds are used to “buy, build, or substantially improve” the home that secures the line of credit. Interest on HELOC funds used for other purposes (debt consolidation, education, vehicles, etc.) is not deductible. The total deductible mortgage debt is capped at $750,000 (combined first mortgage and HELOC). Keep records of how you use HELOC funds to support any tax deduction claims.