HELOC Calculator

Estimate your home equity line of credit limit, then see the monthly payment during the interest-only draw period and the repayment period.

How a HELOC works

A home equity line of credit (HELOC) lets you borrow against the value of your home that you own outright. It works in two stages:

  • Draw period (often 10 years): you can borrow, repay and borrow again. Many HELOCs only require interest payments during this time.
  • Repayment period (often 10–20 years): you can no longer borrow, and the balance is paid off with principal and interest, so the payment usually jumps.

How much can I borrow with a HELOC?

HELOC limit = Home value × max CLTV − mortgage balance

With a $400,000 home, an 85% combined loan-to-value (CLTV) limit and a $250,000 mortgage: $400,000 × 0.85 − $250,000 = $90,000. Lenders also look at your credit score, income and debt-to-income ratio, so your approved limit can be lower.

HELOC payment formulas

Interest-only payment = Balance × (APR ÷ 12) Repayment payment = B × r ÷ (1 − (1 + r)^−n)

Here r is the monthly rate and n is the number of monthly payments. Borrowing $50,000 at 8.5% costs about $354 a month interest-only, then about $434 a month over a 20-year repayment period.

HELOC rates are usually variable, so real payments change when rates move. This calculator assumes the rate stays the same and the full amount is borrowed at the start. Your home secures the loan, so you could lose it if you cannot repay. This is an estimate, not a loan offer.

Frequently asked questions

What is a good CLTV for a HELOC?

Most lenders cap combined loan-to-value at 80–90%. A lower CLTV leaves you more equity as a cushion if home prices fall.

Why does my payment go up after the draw period?

During the draw period many HELOCs only charge interest. In the repayment period you also pay back the principal, which raises the payment.

Is a HELOC better than a cash-out refinance?

A HELOC keeps your existing mortgage rate and lets you borrow only what you need. A cash-out refinance replaces your whole mortgage, which may make sense if the new rate is lower.

Is HELOC interest tax deductible?

In the US, HELOC interest may be deductible if the money is used to buy, build or substantially improve the home that secures it. Check current IRS rules or ask a tax professional.

Does the calculator include fees?

No. Some HELOCs have appraisal fees, annual fees or closing costs. Ask your lender for the full cost.

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