Home Equity & HELOC Calculator

Scope: Supporting copy only. The calculator tool itself is unchanged (CTO owns the calculation logic).

A home equity line of credit (HELOC) lets you borrow against the equity you have built in your home, drawing funds as you need them rather than taking a single lump sum. This calculator estimates how much you may be able to access based on your home’s value, your outstanding mortgage balance, and the maximum combined loan-to-value (CLTV) ratio your lender allows.

The result is an estimate for planning purposes, not a loan offer. Actual limits, rates, and terms depend on your credit profile, income, the lender’s underwriting standards, and an appraisal of your home. Use the figure here to understand roughly what a HELOC could provide, then confirm specifics with lenders before you make decisions.

How this calculator works

The core estimate is straightforward:

Available HELOC ≈ (home value × maximum combined LTV) − current mortgage balance

The maximum combined loan-to-value ratio is the ceiling a lender places on the total of all loans secured by your home, expressed as a share of the home’s appraised value. Most lenders cap HELOC borrowing at roughly 80% to 85% of home value (combined with your existing mortgage), with some going to 90% and a few specialty lenders reaching 95% at higher rates and stricter terms — as of July 2026. Source: The Mortgage Reports — Maximum HELOC Amount / HELOC Limits 2026.

Example: on a home worth $500,000 with an 85% CLTV cap, the lender would allow up to $425,000 in total secured debt. If you still owe $300,000 on your first mortgage, your estimated available HELOC is about $125,000.

Your monthly cost depends on the interest rate. HELOC rates are variable and typically tied to the prime rate plus a lender margin. The national average HELOC rate is roughly in the 7% to 8% range — Bankrate reported a national average of about 7.46% as of July 1, 2026, with the prime rate at 6.75% — as of July 2026. Source: Bankrate — Current HELOC Rates. Because this rate is prime-based, it moves whenever the Federal Reserve changes the federal funds rate, so treat any quoted figure as a snapshot. (This rate is perishable; it is refreshed on a monthly-to-quarterly cadence — see the note to the CTO below.)

Draw period vs. repayment period

A HELOC has two distinct phases, and understanding the difference is essential to avoiding payment shock.

Draw period (commonly 5 to 10 years): You can borrow, repay, and re-borrow up to your credit limit, like a revolving line. During this phase many lenders require only interest-only payments on the balance you have drawn. Payments look low, which is convenient but can be misleading.

Repayment period (commonly 10 to 20 years): The line closes to new draws and you begin paying principal and interest (P&I). Because principal is now included and it is amortized over a shorter remaining term, your monthly payment can jump substantially compared with the draw period.

Two risks compound this. First, the rate is variable — if prime rises, your payment rises even before repayment begins. Second, the shift from interest-only to full P&I at the end of the draw period is a scheduled, and often underestimated, increase. Budget for both.

HELOC vs. home equity loan vs. cash-out refinance

All three tap home equity, but they behave differently:

• HELOC — A revolving line with a variable rate. You draw only what you need during the draw period and pay interest on the balance you use. Best for flexible, ongoing, or uncertain expenses. Rate risk is the main trade-off.
• Home equity loan — A one-time lump sum with a fixed rate and fixed monthly payments over a set term. It leaves your first mortgage untouched. Best when you know the exact amount you need and want payment certainty.
• Cash-out refinance — Replaces your existing mortgage with a new, larger one and gives you the difference in cash. It can make sense if new-mortgage rates are attractive relative to your current rate, but it resets your primary loan and typically carries higher closing costs than a HELOC or home equity loan.

The right choice depends on whether you value flexibility (HELOC), certainty (home equity loan), or consolidating into one primary loan (cash-out refi), and on how current rates compare with your existing mortgage.

Frequently Asked Questions

How much can I borrow with a HELOC?

Roughly your home’s value multiplied by the lender’s maximum CLTV (commonly 80%–85%), minus what you still owe on your mortgage. Lenders also weigh your credit score, income, and debt-to-income ratio, so your actual limit may be lower than the equity math alone suggests. as of July 2026. Source: The Mortgage Reports.

Is HELOC interest tax-deductible?

It can be, but only under specific conditions, and this is general information rather than tax advice. Interest may be deductible when the funds are used to buy, build, or substantially improve the home securing the loan, subject to IRS limits. Interest on funds used for other purposes (for example, paying off credit cards) is generally not deductible. Confirm your situation with a tax professional or current IRS guidance.

How does the variable rate affect my payments?

HELOC rates are usually prime-based, so they change when the prime rate changes. A higher rate increases your interest cost immediately, even during the draw period. When you also transition from interest-only draw payments to principal-and-interest repayment, the combined effect can raise your monthly payment significantly. Stress-test your budget against a higher rate before borrowing.

Are there closing costs on a HELOC?

Often yes, though many lenders advertise low or no upfront closing costs. Possible charges include application, appraisal, annual maintenance, and early-termination fees. “No closing cost” offers sometimes recover the cost through a slightly higher rate or a fee if you close the line early. Ask each lender for a full fee schedule before comparing.

What credit score do I need?

Requirements vary, but many lenders look for a mid-600s score or higher, with the best rates reserved for stronger credit. Lower scores may still qualify at higher rates or lower CLTV limits.

Last reviewed July 3, 2026 by the askdoss Editorial Team. This calculator and its supporting information are for general educational purposes only and are not financial, tax, legal, or investment advice. Figures cited are estimates that change over time — verify current numbers with the relevant institution or a qualified professional before making decisions.