Home Equity Loan Calculator: Amount Up to a CLTV Limit and Payment

This calculator works out how much home equity sits below a combined loan-to-value (CLTV) limit, and the monthly payment on a home equity loan of that size. Enter the home value, what you owe on the mortgage, the CLTV limit to test, the APR and the term. It is arithmetic only, not an offer or an approval.

Formula

Amount = home value × CLTV ÷ 100 − mortgage balance. Payment = amount × r ÷ (1 − (1 + r)⁻ⁿ) with r = APR ÷ 1200. Current LTV = balance ÷ value × 100.

Worked Example

A $400,000 home with $220,000 owed, testing an 80% CLTV limit, 8.5% APR over 15 years.

1. 80% of 400,000 = 320,000; amount = 320,000 − 220,000 = $100,000.00
2. Payment = 100,000 × 0.0070833 ÷ (1 − 1.0070833⁻¹⁸⁰) = $984.74
3. Current LTV = 220,000 ÷ 400,000 × 100 = 55.0%

Assumptions

• Results use the exact level payment before rounding to the cent; a lender’s cent-rounded schedule can differ by a few cents.
• Fixed interest rate for the whole term; payments of equal size at the end of each month.
• Interest compounds monthly at APR ÷ 12.
• No fees, taxes or insurance unless the calculator has a field for them.
• The CLTV limit is a number you enter to test; each lender sets its own limit and its own valuation.

How to read the result

If the balance is already above the limit, the amount shows “Cannot compute”: there is no equity below that limit. A lower CLTV limit leaves more equity untouched.

Limits and common mistakes

• Use a realistic home value; a lender will use its own appraisal.
• Closing costs are not included.

Frequently Asked Questions

How much equity is below 80% CLTV on a $400,000 home with $220,000 owed?

$100,000.

What is the payment on $100,000 at 8.5% over 15 years?

About $984.74 a month.

Is this the amount a lender will lend?

No. Lenders decide using their own limits, valuation and your finances.

in v | Home value | $ | 400000 | 1 | 100000000
in owe | Mortgage balance owed | $ | 220000 | 0 | 100000000
in cl | Combined loan-to-value limit | % | 80 | 1 | 100
in apr | Interest rate (APR) | % | 8.5 | 0.01 | 100
in yrs | Loan term | years | 15 | 1 | 30
out amt | Amount up to the CLTV limit | $ | v * cl / 100 - owe + 0 * sqrt(v * cl / 100 - owe) | 2
out pmt | Monthly payment on that amount | $ | amt * (apr / 1200) / (1 - (1 + apr / 1200) ^ -(yrs * 12)) | 2
out ltv | Current loan-to-value | % | owe / v * 100 | 1