Home equity, CLTV, how much you can borrow and the HELOC payment in draw and repayment
Estimates only, not financial advice. What you type stays on your device. Checked against sources on 6 Oct 2026.A $500,000 home with $280,000 owed has $220,000 of equity. At an 85% maximum combined loan-to-value a lender could lend up to $145,000. Drawing $50,000 at 8.5% costs $354.17 a month interest-only for 10 years, then $433.91 a month over 20 years of repayment.
Rates and rules read from the sources listed on this page (the earliest on 6 Oct 2026); they may have changed since.
Enter the home value and what is still owed on the mortgage and any other loan on the home.
Enter the lender maximum combined loan-to-value; 85% is only an example.
Enter the credit line, the amount you plan to draw, the rate and the draw and repayment years.
Read your equity, the most you could borrow, and the CLTV and HCLTV.
Read the interest-only payment in the draw period and the higher payment once repayment starts.
The HELOC Calculator answers three questions about borrowing against a home: how much equity you have, how much a lender could lend, and what a home equity line of credit would cost each month.
Equity and the ratios. Equity is the home value minus every loan secured on it. LTV is the first mortgage divided by the value. The combined ratios follow Fannie Mae's Selling Guide: CLTV adds other loans and the drawn part of a HELOC (B2-1.2-02), and HCLTV adds the full credit line whether drawn or not (B2-1.2-03). For a purchase Fannie Mae divides by the lower of price and appraised value; for a home you own, enter its current value.
How much you can borrow. Each lender sets a maximum combined loan-to-value, so it is an input; 85% is an example. The borrowable amount is that share of the value minus what you already owe. A line larger than that is flagged.
The payment. Most HELOCs have a draw period, often 10 years, when the minimum payment is the interest on what you have drawn: balance × rate ÷ 12. Then the balance is repaid with principal and interest over the repayment period, often 20 years, using the standard amortization formula. The jump between the two is shown, because it surprises many borrowers.
What it does not do. The rate is held fixed, but most HELOCs are variable and follow the prime rate, so try a higher rate as well. Further draws during the draw period, minimum payments that include principal, annual fees, closing costs and tax deductions are not modelled. Every figure shown at first is an example; use your lender's terms. For a new first mortgage instead, see the Refinance Calculator.
Lenders cap the total of all loans on the home at a maximum combined loan-to-value they set. With an 85% limit, a $500,000 home with $280,000 owed allows $425,000 in total, so up to $145,000 more. Credit score, income and debts can lower the line a lender actually offers.
During the draw period most HELOCs require only the interest on the amount drawn: balance × yearly rate ÷ 12. On $50,000 at 8.5% that is $354.17 a month. Nothing is repaid, so the balance stays at $50,000 unless you pay extra. Some lenders require a little principal as well.
The balance is then repaid with principal and interest over the repayment period. Repaying $50,000 at 8.5% over 20 years costs $433.91 a month, $79.74 more than the interest-only payment. With a larger balance or a higher variable rate the jump is larger, so plan for it early.
Both add every loan on the home and divide by its value. Fannie Mae's CLTV counts only the drawn part of a HELOC; HCLTV counts the full credit line, drawn or not. With $50,000 drawn of a $100,000 line, HCLTV is 10 points higher than CLTV on a $500,000 home.
Most HELOC rates are variable, usually the prime rate plus a margin, and change during the loan. The calculator holds the rate you enter fixed, so run it again at a rate one or two points higher. A home equity loan, by contrast, usually has a fixed rate and a fixed payment from the start.
Later draws, minimum payments that include principal, annual fees, closing costs, rate caps and tax deductions are not modelled. The value of the home is your input, not an appraisal. Lenders also check credit, income and debts, so the line offered can be lower than the maximum shown.
Rates and rules change; check the source before you rely on a figure.
Still stuck? Ask about HELOC Calculator and anybody who knows can answer. No account needed.
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Also works as: Home Equity Calculator · HELOC Payment Calculator.
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