For informational purposes only. Not financial, investment, or tax advice. Results are estimates based on the inputs provided. Consult a qualified financial professional before making financial decisions.
Calculator tool
How this calculator works
Use the explanation to understand the formula, assumptions, and practical limits behind the calculator result.
What a HELOC Measures
A HELOC is a revolving line of credit secured by home equity. This calculator estimates how much room may exist under the loan-to-value limit you enter, then shows the effect of drawing part of that line.
Credit-Line Formula
If the result is below zero, the available line is shown as zero because there is no room left under the entered cap.
Draw Amount and Interest-Only Payment
The payment estimate uses only the amount drawn, not the unused credit line.
Where:
- = monthly interest-only payment
- = amount drawn
- = annual interest rate as a decimal
| Result | Meaning |
|---|---|
| Credit line limit | Estimated maximum line under the entered LTV cap |
| Amount drawn | Balance currently used |
| Available credit | Unused part of the line after the draw |
| Monthly interest-only payment | Interest on the drawn balance at the entered rate |
Important HELOC Caveats
Many HELOCs use variable rates, so the payment can change when the index or margin changes. A draw period may allow interest-only payments, while a later repayment period can require principal plus interest. A lender can also use its own appraisal, CLTV cap, fees, and qualification rules, so the final approved line can differ from this estimate.
Use the calculator to test borrowing capacity and payment sensitivity, then verify the exact terms in the lender's agreement before relying on the number.
Frequently asked questions
What is the difference between a HELOC and a home equity loan?
A HELOC is a revolving line you can draw from, repay, and potentially draw again during the allowed period. A home equity loan is usually a one-time lump sum with a fixed repayment schedule. The HELOC offers flexibility; the loan offers more predictable payments.
Why does the payment use the draw amount instead of the whole credit line?
Because interest is charged on the balance actually borrowed, not on unused available credit. If a line is approved for 20,000 is drawn, the interest-only payment is based on the $20,000 balance.
What risk matters most with a HELOC?
Payment risk. Variable rates can move, and a future repayment period can require principal in addition to interest. A payment that looks comfortable during the draw period may be materially higher later.
Is HELOC interest always tax-deductible?
No. In the US, deductibility can depend on how the proceeds are used and other tax rules. Interest used to buy, build, or substantially improve the home securing the loan may be treated differently from interest used for consumer spending. Verify the current rule with a qualified tax professional.
