Home Equity Loan Calculator: Estimate Monthly Payments

A home equity loan calculator estimates the fixed monthly payment and total interest on a lump-sum loan secured by home equity. Enter the loan amount, annual percentage rate (APR), and term to see the estimated payment and interest; use figures supplied by a lender for a more relevant estimate.

Formula

The calculator uses the standard level-payment formula for an installment loan with a fixed rate and monthly payments. It rounds the monthly payment to the nearest cent before calculating total interest.

• Monthly payment: M = round(P × r ÷ [1 − (1 + r)⁻ⁿ], 2)
• Total interest: I = M × n − P
• Monthly rate: r = APR ÷ 1,200
• Number of payments: n = loan term in years × 12

P is the amount borrowed in dollars, APR is the annual percentage rate entered as a percentage, r is the monthly rate as a decimal, n is the number of monthly payments, M is the monthly payment in dollars, and I is estimated total interest in dollars. The APR input is divided by 1,200 because it is expressed as a percentage per year and converted to a monthly decimal rate.

Worked Example

Using the calculator’s default inputs—$20,000 borrowed, 8% APR, and a five-year term:

1. Convert the APR to a monthly rate: 8 ÷ 1,200 = 0.0066667.
2. Convert the term to payments: 5 × 12 = 60 months.
3. Apply the payment formula: $20,000 × 0.0066667 ÷ [1 − (1.0066667)⁻⁶⁰] = $405.53 after rounding to cents.
4. Calculate total interest using the rounded payment: $405.53 × 60 − $20,000 = $4,331.80.

The estimate is therefore a monthly payment of $405.53 and total interest of $4,331.80. The payment multiplied by 60 is $24,331.80, of which $20,000 is principal and $4,331.80 is interest.

Assumptions

• The interest rate remains fixed for the full term.
• Payments are equal, made monthly, and begin on schedule; the calculation does not model a specific payment date.
• Interest is calculated monthly using APR divided by 12.
• Fees, taxes, insurance, escrow, and other charges are not included. The calculator also does not model closing costs, optional extra payments, or late payments.

How to Use the Estimate

A home equity loan generally provides a borrower with a lump sum that is repaid over an agreed term. This differs from a home equity line of credit, which allows borrowing and repayment through a credit line under its own terms. This calculator estimates only the payment and interest for a fixed-rate, fully amortizing lump-sum loan; it does not calculate a credit line’s changing balance or payment.

Enter the amount you intend to borrow, not the value of the home or the equity shown on a statement. Use the proposed loan’s APR and term when available. APR is an annualized rate figure, but the calculation assumes a monthly rate equal to APR divided by 12. The lender’s payment schedule and fee treatment may differ, so compare the result with the formal loan disclosure rather than treating this estimate as a quoted payment.

• Monthly payment is the estimated principal-and-interest amount due each month.
• Total interest is the estimated interest paid over all scheduled payments, using the rounded monthly payment.
• Total of scheduled payments can be read as the loan amount plus total interest. It does not include costs omitted from the inputs.

Choosing Inputs and Understanding Costs

The loan amount, APR, and term affect the estimate in different ways. A larger principal generally raises the payment and total interest. At the same principal and term, a higher APR raises the payment. A longer term usually lowers the required monthly payment but spreads repayment over more months, which can increase total interest. The exact result depends on the entered figures and the loan’s terms; the calculator does not decide whether a particular payment is suitable.

Obtain the actual rate, term, payment timing, and any charges from the lender’s written materials. Fees may be paid upfront, included in the amount financed, or handled in another way. Since this calculator has no fee input, it cannot reflect those differences. Do not add a fee to the loan amount unless that is how the loan is structured and the amount being entered represents the actual principal.

Home equity is not the same as available borrowing. A home’s estimated value minus outstanding mortgage balances is a rough equity calculation, but a lender may use its own valuation and underwriting process. This calculator does not estimate a home’s value, available loan amount, eligibility, or approval, and its upper input limit is a technical calculator boundary rather than a lending limit.

Common Calculation Limits and Errors

A common mistake is to enter a whole-number APR as a decimal—for example, enter 8 for 8%, not 0.08. Another is to enter the term in months even though this calculator asks for years. Check whether the amount entered is the proposed loan principal rather than total debt or home value.

The formula assumes regular equal payments and a positive APR. It is not designed for changing rates, interest-only periods, balloon payments, skipped payments, or irregular schedules. It also does not include fees or predict how a lender will calculate interest on particular dates. Rounding the monthly payment to cents means the final payment on a real loan may differ slightly from the estimate to settle the exact remaining balance.

The result is arithmetic, not financial advice. Consider the lender’s documents for the actual terms and all charges, and seek qualified help for questions about individual circumstances.

Frequently Asked Questions

What does a home equity loan calculator calculate?
It estimates the monthly principal-and-interest payment and total interest for a lump-sum loan from the principal, APR, and repayment term entered.

Is a home equity loan the same as a HELOC?
No. A home equity loan is generally a lump-sum installment loan. A HELOC is a credit line with borrowing and repayment features that are not represented by this fixed-payment calculator.

Does the monthly payment include fees or taxes?
No. This estimate includes principal and interest only. It does not include fees, taxes, insurance, escrow, or other charges unless those costs are reflected in the principal or otherwise specified by the lender.

Why can a longer term reduce the monthly payment but raise total interest?
A longer term divides repayment across more monthly payments, which can lower each payment. Interest accrues over a longer period, so total interest can be higher even when the monthly amount is lower.

Can this calculator tell me how much I can borrow?
No. It calculates payments for a loan amount you enter. It does not determine home value, available equity, approval, or a lender’s borrowing limit.

The result is an estimate, and the lender’s disclosure gives the exact figures.

Related

• Home Equity Loan Calculator: Amount Up to a CLTV Limit and Payment
• Mortgage Calculator With Escrow: Payment With Tax and Insurance
• Mortgage Loan Amount Calculator: The Loan a Monthly Payment Repays

in p | Loan amount | $ | 20000 | 1 | 100000000
in apr | Interest rate (APR) | % | 8 | 0.01 | 100
in yrs | Loan term | years | 5 | 0.0833 | 50
out pmt | Monthly payment | $ | round(p * (apr / 1200) / (1 - (1 + apr / 1200) ^ -(yrs * 12)), 2) | 2
out int | Total interest | $ | pmt * yrs * 12 - p | 2