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Printed July 28, 2026 · https://trycleartally.com/heloc-calculator
Estimates for educational purposes only — not financial advice. See https://trycleartally.com/disclaimer.
HELOC Calculator
See how much you could borrow against your home's equity, and what the payments look like — interest-only during the draw period, then higher once repayment begins.
Reviewed by the ClearTally editorial team · Last updated July 26, 2026 · Methodology & sources
Lender's cap on total borrowing — often 80–90%.
How much of the line you'd draw.
Available credit line
$90,000
Up to 85% of your home value, minus your mortgage
Draw period payment
$354.17
Interest-only, per month
Repayment period payment
$433.91
Principal + interest, per month
Combined loan-to-value
75.0%
Mortgage + HELOC vs. home value
Total interest
$96,639
Over both phases
Heads up: when the draw period ends, the payment jumps about $79.74/month — from interest-only to paying down the balance. That step-up is the part HELOC borrowers most often get caught by.
HELOC rates are usually variable, so your real payment moves with rates over time — this holds the rate constant as a snapshot. It also assumes you draw the amount once up front; drawing gradually lowers early interest. Lender LTV caps, credit, and income all affect what you're actually offered. Estimate only, not a loan offer or financial advice.
HELOC Estimate
Available credit line
$90,000
HELOC rates are typically variable; this holds the rate constant. Assumes a single up-front draw. Not a loan offer.
Calculated using the standard formulas described at https://trycleartally.com/methodology — for educational estimates only, not a quote or financial advice. Verify with your lender or financial institution before making decisions.
Weighing how to tap your equity? A cash-out refinance replaces your whole mortgage instead of adding a second loan, and the mortgage payoff calculator shows how fast extra payments build the equity a HELOC borrows against.
How it works
A home equity line of credit lets you borrow against the equity you've built, up to a limit set by your lender. That limit is your home's value times a maximum combined loan-to-value — often 80% to 90% — minus what you still owe on your mortgage. Whatever's left is your available credit line, which you can draw from as needed rather than taking as a lump sum.
A HELOC runs in two phases, and the gap between them is the thing to understand before you sign. During the draw period (commonly 10 years) many lenders let you pay interest only, which keeps payments low. When the repayment period begins, you can no longer draw and you start paying down the balance too — so the payment steps up, sometimes sharply. Because most HELOCs carry a variable rate tied to the prime rate, the real payment also moves as rates change; this calculator holds the rate steady as a snapshot.
Example:a $400,000 home with $250,000 left on the mortgage, at an 85% max LTV, gives about $90,000 of available credit (400,000 × 0.85 = 340,000, minus the 250,000 owed). Draw $50,000 at 8.5% and the interest-only payment during the draw period is roughly $354 a month. Once repayment starts over 20 years, it rises to about $434 — a jump of some $80 a month, and that's before any rate increase.
FAQ
Take your home's value, multiply by your lender's maximum combined loan-to-value (typically 80–90%), and subtract your current mortgage balance. On a $400,000 home at 85% LTV, the lender caps total borrowing at $340,000; if you owe $250,000, that leaves about $90,000 available. 'Combined' matters because the cap counts your first mortgage and the HELOC together. The final number also depends on your credit, income, and the lender's own limits, so treat this as an upper-bound estimate.